1 /*
2  * Copyright (c) 2007 Mockito contributors
3  * This program is made available under the terms of the MIT License.
4  */
5 package org.mockito;
6 
7 import org.mockito.exceptions.misusing.PotentialStubbingProblem;
8 import org.mockito.exceptions.misusing.UnnecessaryStubbingException;
9 import org.mockito.internal.InternalMockHandler;
10 import org.mockito.internal.MockitoCore;
11 import org.mockito.internal.creation.MockSettingsImpl;
12 import org.mockito.internal.debugging.MockitoDebuggerImpl;
13 import org.mockito.internal.framework.DefaultMockitoFramework;
14 import org.mockito.internal.session.DefaultMockitoSessionBuilder;
15 import org.mockito.internal.verification.VerificationModeFactory;
16 import org.mockito.invocation.Invocation;
17 import org.mockito.invocation.InvocationFactory;
18 import org.mockito.invocation.MockHandler;
19 import org.mockito.junit.MockitoJUnit;
20 import org.mockito.junit.MockitoJUnitRunner;
21 import org.mockito.junit.MockitoRule;
22 import org.mockito.listeners.VerificationStartedEvent;
23 import org.mockito.listeners.VerificationStartedListener;
24 import org.mockito.mock.SerializableMode;
25 import org.mockito.plugins.MockMaker;
26 import org.mockito.plugins.MockitoPlugins;
27 import org.mockito.quality.MockitoHint;
28 import org.mockito.quality.Strictness;
29 import org.mockito.session.MockitoSessionBuilder;
30 import org.mockito.session.MockitoSessionLogger;
31 import org.mockito.stubbing.Answer;
32 import org.mockito.stubbing.Answer1;
33 import org.mockito.stubbing.LenientStubber;
34 import org.mockito.stubbing.OngoingStubbing;
35 import org.mockito.stubbing.Stubber;
36 import org.mockito.stubbing.Stubbing;
37 import org.mockito.stubbing.VoidAnswer1;
38 import org.mockito.verification.After;
39 import org.mockito.verification.Timeout;
40 import org.mockito.verification.VerificationAfterDelay;
41 import org.mockito.verification.VerificationMode;
42 import org.mockito.verification.VerificationWithTimeout;
43 
44 /**
45  * <p align="left"><img src="logo.png" srcset="logo@2x.png 2x" alt="Mockito logo"/></p>
46  * The Mockito library enables mock creation, verification and stubbing.
47  *
48  * <p>
49  * This javadoc content is also available on the <a href="http://mockito.org">http://mockito.org</a> web page.
50  * All documentation is kept in javadocs because it guarantees consistency between what's on the web and what's in the source code.
51  * It allows access to documentation straight from the IDE even if you work offline.
52  * It motivates Mockito developers to keep documentation up-to-date with the code that they write,
53  * every day, with every commit.
54  *
55  * <h1>Contents</h1>
56  *
57  * <b>
58  *      <a href="#0">0. Migrating to Mockito 2</a><br/>
59  *      <a href="#0.1">0.1 Mockito Android support</a></br/>
60  *      <a href="#0.2">0.2 Configuration-free inline mock making</a></br/>
61  *      <a href="#1">1. Let's verify some behaviour! </a><br/>
62  *      <a href="#2">2. How about some stubbing? </a><br/>
63  *      <a href="#3">3. Argument matchers </a><br/>
64  *      <a href="#4">4. Verifying exact number of invocations / at least once / never </a><br/>
65  *      <a href="#5">5. Stubbing void methods with exceptions </a><br/>
66  *      <a href="#6">6. Verification in order </a><br/>
67  *      <a href="#7">7. Making sure interaction(s) never happened on mock </a><br/>
68  *      <a href="#8">8. Finding redundant invocations </a><br/>
69  *      <a href="#9">9. Shorthand for mocks creation - <code>&#064;Mock</code> annotation </a><br/>
70  *      <a href="#10">10. Stubbing consecutive calls (iterator-style stubbing) </a><br/>
71  *      <a href="#11">11. Stubbing with callbacks </a><br/>
72  *      <a href="#12">12. <code>doReturn()</code>|<code>doThrow()</code>|<code>doAnswer()</code>|<code>doNothing()</code>|<code>doCallRealMethod()</code> family of methods</a><br/>
73  *      <a href="#13">13. Spying on real objects </a><br/>
74  *      <a href="#14">14. Changing default return values of unstubbed invocations (Since 1.7) </a><br/>
75  *      <a href="#15">15. Capturing arguments for further assertions (Since 1.8.0) </a><br/>
76  *      <a href="#16">16. Real partial mocks (Since 1.8.0) </a><br/>
77  *      <a href="#17">17. Resetting mocks (Since 1.8.0) </a><br/>
78  *      <a href="#18">18. Troubleshooting & validating framework usage (Since 1.8.0) </a><br/>
79  *      <a href="#19">19. Aliases for behavior driven development (Since 1.8.0) </a><br/>
80  *      <a href="#20">20. Serializable mocks (Since 1.8.1) </a><br/>
81  *      <a href="#21">21. New annotations: <code>&#064;Captor</code>, <code>&#064;Spy</code>, <code>&#064;InjectMocks</code> (Since 1.8.3) </a><br/>
82  *      <a href="#22">22. Verification with timeout (Since 1.8.5) </a><br/>
83  *      <a href="#23">23. Automatic instantiation of <code>&#064;Spies</code>, <code>&#064;InjectMocks</code> and constructor injection goodness (Since 1.9.0)</a><br/>
84  *      <a href="#24">24. One-liner stubs (Since 1.9.0)</a><br/>
85  *      <a href="#25">25. Verification ignoring stubs (Since 1.9.0)</a><br/>
86  *      <a href="#26">26. Mocking details (Improved in 2.2.x)</a><br/>
87  *      <a href="#27">27. Delegate calls to real instance (Since 1.9.5)</a><br/>
88  *      <a href="#28">28. <code>MockMaker</code> API (Since 1.9.5)</a><br/>
89  *      <a href="#29">29. BDD style verification (Since 1.10.0)</a><br/>
90  *      <a href="#30">30. Spying or mocking abstract classes (Since 1.10.12, further enhanced in 2.7.13 and 2.7.14)</a><br/>
91  *      <a href="#31">31. Mockito mocks can be <em>serialized</em> / <em>deserialized</em> across classloaders (Since 1.10.0)</a></h3><br/>
92  *      <a href="#32">32. Better generic support with deep stubs (Since 1.10.0)</a></h3><br/>
93  *      <a href="#33">33. Mockito JUnit rule (Since 1.10.17)</a><br/>
94  *      <a href="#34">34. Switch <em>on</em> or <em>off</em> plugins (Since 1.10.15)</a><br/>
95  *      <a href="#35">35. Custom verification failure message (Since 2.1.0)</a><br/>
96  *      <a href="#36">36. Java 8 Lambda Matcher Support (Since 2.1.0)</a><br/>
97  *      <a href="#37">37. Java 8 Custom Answer Support (Since 2.1.0)</a><br/>
98  *      <a href="#38">38. Meta data and generic type retention (Since 2.1.0)</a><br/>
99  *      <a href="#39">39. Mocking final types, enums and final methods (Since 2.1.0)</a><br/>
100  *      <a href="#40">40. Improved productivity and cleaner tests with "stricter" Mockito (Since 2.+)</a><br/>
101  *      <a href="#41">41. Advanced public API for framework integrations (Since 2.10.+)</a><br/>
102  *      <a href="#42">42. New API for integrations: listening on verification start events (Since 2.11.+)</a><br/>
103  *      <a href="#43">43. New API for integrations: <code>MockitoSession</code> is usable by testing frameworks (Since 2.15.+)</a><br/>
104  *      <a href="#44">44. Deprecated <code>org.mockito.plugins.InstantiatorProvider</code> as it was leaking internal API. it was replaced by <code>org.mockito.plugins.InstantiatorProvider2 (Since 2.15.4)</code></a><br/>
105  *      <a href="#45">45. New JUnit Jupiter (JUnit5+) extension</a><br/>
106  *      <a href="#46">46. New <code>Mockito.lenient()</code> and <code>MockSettings.lenient()</code> methods (Since 2.20.0</a><br/>
107  * </b>
108  *
109  * <h3 id="0">0. <a class="meaningful_link" href="#mockito2" name="mockito2">Migrating to Mockito 2</a></h3>
110  *
111  * In order to continue improving Mockito and further improve the unit testing experience, we want you to upgrade to 2.1.0!
112  * Mockito follows <a href="http://semver.org/">semantic versioning</a> and contains breaking changes only on major version upgrades.
113  * In the lifecycle of a library, breaking changes are necessary
114  * to roll out a set of brand new features that alter the existing behavior or even change the API.
115  * For a comprehensive guide on the new release including incompatible changes,
116  * see '<a href="https://github.com/mockito/mockito/wiki/What%27s-new-in-Mockito-2">What's new in Mockito 2</a>' wiki page.
117  * We hope that you enjoy Mockito 2!
118  *
119  * <h3 id="0.1">0.1. <a class="meaningful_link" href="#mockito-android" name="mockito-android">Mockito Android support</a></h3>
120  *
121  * With Mockito version 2.6.1 we ship "native" Android support. To enable Android support, add the `mockito-android` library as dependency
122  * to your project. This artifact is published to the same Mockito organization and can be imported for Android as follows:
123  *
124  * <pre class="code"><code>
125  * repositories {
126  *   jcenter()
127  * }
128  * dependencies {
129  *   testCompile "org.mockito:mockito-core:+"
130  *   androidTestCompile "org.mockito:mockito-android:+"
131  * }
132  * </code></pre>
133  *
134  * You can continue to run the same unit tests on a regular VM by using the `mockito-core` artifact in your "testCompile" scope as shown
135  * above. Be aware that you cannot use the <a href="#39">inline mock maker</a> on Android due to limitations in the Android VM.
136  *
137  * If you encounter issues with mocking on Android, please open an issue
138  * <a href="https://github.com/mockito/mockito/issues/new">on the official issue tracker</a>.
139  * Do provide the version of Android you are working on and dependencies of your project.
140  *
141  * <h3 id="0.2">0.2. <a class="meaningful_link" href="#mockito-inline" name="mockito-inline">Configuration-free inline mock making</a></h3>
142  *
143  * Starting with version 2.7.6, we offer the 'mockito-inline' artifact that enables <a href="#39">inline mock making</a> without configuring
144  * the MockMaker extension file. To use this, add the `mockito-inline` instead of the `mockito-core` artifact as follows:
145  *
146  * <pre class="code"><code>
147  * repositories {
148  *   jcenter()
149  * }
150  * dependencies {
151  *   testCompile "org.mockito:mockito-inline:+"
152  * }
153  * </code></pre>
154  *
155  * Be aware that this artifact may be abolished when the inline mock making feature is integrated into the default mock maker.
156  *
157  * <p>
158  * For more information about inline mock making, see <a href="#39">section 39</a>.
159  *
160  * <h3 id="1">1. <a class="meaningful_link" href="#verification" name="verification">Let's verify some behaviour!</a></h3>
161  *
162  * The following examples mock a List, because most people are familiar with the interface (such as the
163  * <code>add()</code>, <code>get()</code>, <code>clear()</code> methods). <br>
164  * In reality, please don't mock the List class. Use a real instance instead.
165  *
166  * <pre class="code"><code class="java">
167  * //Let's import Mockito statically so that the code looks clearer
168  * import static org.mockito.Mockito.*;
169  *
170  * //mock creation
171  * List mockedList = mock(List.class);
172  *
173  * //using mock object
174  * mockedList.add("one");
175  * mockedList.clear();
176  *
177  * //verification
178  * verify(mockedList).add("one");
179  * verify(mockedList).clear();
180  * </code></pre>
181  *
182  * <p>
183  * Once created, a mock will remember all interactions. Then you can selectively
184  * verify whatever interactions you are interested in.
185  * </p>
186  *
187  *
188  *
189  * <h3 id="2">2. <a class="meaningful_link" href="#stubbing" name="stubbing">How about some stubbing?</a></h3>
190  *
191  * <pre class="code"><code class="java">
192  * //You can mock concrete classes, not just interfaces
193  * LinkedList mockedList = mock(LinkedList.class);
194  *
195  * //stubbing
196  * when(mockedList.get(0)).thenReturn("first");
197  * when(mockedList.get(1)).thenThrow(new RuntimeException());
198  *
199  * //following prints "first"
200  * System.out.println(mockedList.get(0));
201  *
202  * //following throws runtime exception
203  * System.out.println(mockedList.get(1));
204  *
205  * //following prints "null" because get(999) was not stubbed
206  * System.out.println(mockedList.get(999));
207  *
208  * //Although it is possible to verify a stubbed invocation, usually <b>it's just redundant</b>
209  * //If your code cares what get(0) returns, then something else breaks (often even before verify() gets executed).
210  * //If your code doesn't care what get(0) returns, then it should not be stubbed. Not convinced? See <a href="http://monkeyisland.pl/2008/04/26/asking-and-telling">here</a>.
211  * verify(mockedList).get(0);
212  * </code></pre>
213  *
214  * <ul>
215  * <li> By default, for all methods that return a value, a mock will return either null,
216  * a primitive/primitive wrapper value, or an empty collection, as appropriate.
217  * For example 0 for an int/Integer and false for a boolean/Boolean. </li>
218  *
219  * <li> Stubbing can be overridden: for example common stubbing can go to
220  * fixture setup but the test methods can override it.
221  * Please note that overridding stubbing is a potential code smell that points out too much stubbing</li>
222  *
223  * <li> Once stubbed, the method will always return a stubbed value, regardless
224  * of how many times it is called. </li>
225  *
226  * <li> Last stubbing is more important - when you stubbed the same method with
227  * the same arguments many times.
228  * Other words: <b>the order of stubbing matters</b> but it is only meaningful rarely,
229  * e.g. when stubbing exactly the same method calls or sometimes when argument matchers are used, etc.</li>
230  *
231  * </ul>
232  *
233  *
234  *
235  * <h3 id="3">3. <a class="meaningful_link" href="#argument_matchers" name="argument_matchers">Argument matchers</a></h3>
236  *
237  * Mockito verifies argument values in natural java style: by using an <code>equals()</code> method.
238  * Sometimes, when extra flexibility is required then you might use argument matchers:
239  *
240  * <pre class="code"><code class="java">
241  * //stubbing using built-in anyInt() argument matcher
242  * when(mockedList.get(anyInt())).thenReturn("element");
243  *
244  * //stubbing using custom matcher (let's say isValid() returns your own matcher implementation):
245  * when(mockedList.contains(argThat(isValid()))).thenReturn("element");
246  *
247  * //following prints "element"
248  * System.out.println(mockedList.get(999));
249  *
250  * //<b>you can also verify using an argument matcher</b>
251  * verify(mockedList).get(anyInt());
252  *
253  * //<b>argument matchers can also be written as Java 8 Lambdas</b>
254  * verify(mockedList).add(argThat(someString -> someString.length() > 5));
255  *
256  * </code></pre>
257  *
258  * <p>
259  * Argument matchers allow flexible verification or stubbing.
260  * {@link ArgumentMatchers Click here} {@link org.mockito.hamcrest.MockitoHamcrest or here} to see more built-in matchers
261  * and examples of <b>custom argument matchers / hamcrest matchers</b>.
262  * <p>
263  * For information solely on <b>custom argument matchers</b> check out javadoc for {@link ArgumentMatcher} class.
264  * <p>
265  * Be reasonable with using complicated argument matching.
266  * The natural matching style using <code>equals()</code> with occasional <code>anyX()</code> matchers tend to give clean & simple tests.
267  * Sometimes it's just better to refactor the code to allow <code>equals()</code> matching or even implement <code>equals()</code> method to help out with testing.
268  * <p>
269  * Also, read <a href="#15">section 15</a> or javadoc for {@link ArgumentCaptor} class.
270  * {@link ArgumentCaptor} is a special implementation of an argument matcher that captures argument values for further assertions.
271  * <p>
272  * <b>Warning on argument matchers:</b>
273  * <p>
274  * If you are using argument matchers, <b>all arguments</b> have to be provided
275  * by matchers.
276  * <p>
277  The following example shows verification but the same applies to stubbing:
278  *
279  * <pre class="code"><code class="java">
280  *   verify(mock).someMethod(anyInt(), anyString(), <b>eq("third argument")</b>);
281  *   //above is correct - eq() is also an argument matcher
282  *
283  *   verify(mock).someMethod(anyInt(), anyString(), <b>"third argument"</b>);
284  *   //above is incorrect - exception will be thrown because third argument is given without an argument matcher.
285  * </code></pre>
286  *
287  * <p>
288  * Matcher methods like <code>anyObject()</code>, <code>eq()</code> <b>do not</b> return matchers.
289  * Internally, they record a matcher on a stack and return a dummy value (usually null).
290  * This implementation is due to static type safety imposed by the java compiler.
291  * The consequence is that you cannot use <code>anyObject()</code>, <code>eq()</code> methods outside of verified/stubbed method.
292  *
293  *
294  *
295  *
296  * <h3 id="4">4. <a class="meaningful_link" href="#exact_verification" name="exact_verification">Verifying exact number of invocations</a> /
297  * <a class="meaningful_link" href="#at_least_verification" name="at_least_verification">at least x</a> / never</h3>
298  *
299  * <pre class="code"><code class="java">
300  * //using mock
301  * mockedList.add("once");
302  *
303  * mockedList.add("twice");
304  * mockedList.add("twice");
305  *
306  * mockedList.add("three times");
307  * mockedList.add("three times");
308  * mockedList.add("three times");
309  *
310  * //following two verifications work exactly the same - times(1) is used by default
311  * verify(mockedList).add("once");
312  * verify(mockedList, times(1)).add("once");
313  *
314  * //exact number of invocations verification
315  * verify(mockedList, times(2)).add("twice");
316  * verify(mockedList, times(3)).add("three times");
317  *
318  * //verification using never(). never() is an alias to times(0)
319  * verify(mockedList, never()).add("never happened");
320  *
321  * //verification using atLeast()/atMost()
322  * verify(mockedList, atLeastOnce()).add("three times");
323  * verify(mockedList, atLeast(2)).add("three times");
324  * verify(mockedList, atMost(5)).add("three times");
325  *
326  * </code></pre>
327  *
328  * <p>
329  * <b>times(1) is the default.</b> Therefore using times(1) explicitly can be
330  * omitted.
331  *
332  *
333  *
334  *
335  * <h3 id="5">5. <a class="meaningful_link" href="#stubbing_with_exceptions" name="stubbing_with_exceptions">Stubbing void methods with exceptions</a></h3>
336  *
337  * <pre class="code"><code class="java">
338  *   doThrow(new RuntimeException()).when(mockedList).clear();
339  *
340  *   //following throws RuntimeException:
341  *   mockedList.clear();
342  * </code></pre>
343  *
344  * Read more about <code>doThrow()</code>|<code>doAnswer()</code> family of methods in <a href="#12">section 12</a>.
345  * <p>
346  *
347  * <h3 id="6">6. <a class="meaningful_link" href="#in_order_verification" name="in_order_verification">Verification in order</a></h3>
348  *
349  * <pre class="code"><code class="java">
350  * // A. Single mock whose methods must be invoked in a particular order
351  * List singleMock = mock(List.class);
352  *
353  * //using a single mock
354  * singleMock.add("was added first");
355  * singleMock.add("was added second");
356  *
357  * //create an inOrder verifier for a single mock
358  * InOrder inOrder = inOrder(singleMock);
359  *
360  * //following will make sure that add is first called with "was added first, then with "was added second"
361  * inOrder.verify(singleMock).add("was added first");
362  * inOrder.verify(singleMock).add("was added second");
363  *
364  * // B. Multiple mocks that must be used in a particular order
365  * List firstMock = mock(List.class);
366  * List secondMock = mock(List.class);
367  *
368  * //using mocks
369  * firstMock.add("was called first");
370  * secondMock.add("was called second");
371  *
372  * //create inOrder object passing any mocks that need to be verified in order
373  * InOrder inOrder = inOrder(firstMock, secondMock);
374  *
375  * //following will make sure that firstMock was called before secondMock
376  * inOrder.verify(firstMock).add("was called first");
377  * inOrder.verify(secondMock).add("was called second");
378  *
379  * // Oh, and A + B can be mixed together at will
380  * </code></pre>
381  *
382  * Verification in order is flexible - <b>you don't have to verify all
383  * interactions</b> one-by-one but only those that you are interested in
384  * testing in order.
385  * <p>
386  * Also, you can create an InOrder object passing only the mocks that are relevant for
387  * in-order verification.
388  *
389  *
390  *
391  *
392  * <h3 id="7">7. <a class="meaningful_link" href="#never_verification" name="never_verification">Making sure interaction(s) never happened on mock</a></h3>
393  *
394  * <pre class="code"><code class="java">
395  * //using mocks - only mockOne is interacted
396  * mockOne.add("one");
397  *
398  * //ordinary verification
399  * verify(mockOne).add("one");
400  *
401  * //verify that method was never called on a mock
402  * verify(mockOne, never()).add("two");
403  *
404  * //verify that other mocks were not interacted
405  * verifyZeroInteractions(mockTwo, mockThree);
406  *
407  * </code></pre>
408  *
409  *
410  *
411  *
412  * <h3 id="8">8. <a class="meaningful_link" href="#finding_redundant_invocations" name="finding_redundant_invocations">Finding redundant invocations</a></h3>
413  *
414  * <pre class="code"><code class="java">
415  * //using mocks
416  * mockedList.add("one");
417  * mockedList.add("two");
418  *
419  * verify(mockedList).add("one");
420  *
421  * //following verification will fail
422  * verifyNoMoreInteractions(mockedList);
423  * </code></pre>
424  *
425  * A word of <b>warning</b>:
426  * Some users who did a lot of classic, expect-run-verify mocking tend to use <code>verifyNoMoreInteractions()</code> very often, even in every test method.
427  * <code>verifyNoMoreInteractions()</code> is not recommended to use in every test method.
428  * <code>verifyNoMoreInteractions()</code> is a handy assertion from the interaction testing toolkit. Use it only when it's relevant.
429  * Abusing it leads to <strong>overspecified</strong>, <strong>less maintainable</strong> tests. You can find further reading
430  * <a href="http://monkeyisland.pl/2008/07/12/should-i-worry-about-the-unexpected/">here</a>.
431  *
432  * <p>
433  * See also {@link Mockito#never()} - it is more explicit and
434  * communicates the intent well.
435  * <p>
436  *
437  *
438  *
439  *
440  * <h3 id="9">9. <a class="meaningful_link" href="#mock_annotation" name="mock_annotation">Shorthand for mocks creation - <code>&#064;Mock</code> annotation</a></h3>
441  *
442  * <ul>
443  * <li>Minimizes repetitive mock creation code.</li>
444  * <li>Makes the test class more readable.</li>
445  * <li>Makes the verification error easier to read because the <b>field name</b>
446  * is used to identify the mock.</li>
447  * </ul>
448  *
449  * <pre class="code"><code class="java">
450  *   public class ArticleManagerTest {
451  *
452  *       &#064;Mock private ArticleCalculator calculator;
453  *       &#064;Mock private ArticleDatabase database;
454  *       &#064;Mock private UserProvider userProvider;
455  *
456  *       private ArticleManager manager;
457  * </code></pre>
458  *
459  * <b>Important!</b> This needs to be somewhere in the base class or a test
460  * runner:
461  *
462  * <pre class="code"><code class="java">
463  * MockitoAnnotations.initMocks(testClass);
464  * </code></pre>
465  *
466  * You can use built-in runner: {@link MockitoJUnitRunner} or a rule: {@link MockitoRule}.
467  * <p>
468  * Read more here: {@link MockitoAnnotations}
469  *
470  *
471  *
472  *
473  * <h3 id="10">10. <a class="meaningful_link" href="#stubbing_consecutive_calls" name="stubbing_consecutive_calls">Stubbing consecutive calls</a> (iterator-style stubbing)</h3>
474  *
475  * Sometimes we need to stub with different return value/exception for the same
476  * method call. Typical use case could be mocking iterators.
477  * Original version of Mockito did not have this feature to promote simple mocking.
478  * For example, instead of iterators one could use {@link Iterable} or simply
479  * collections. Those offer natural ways of stubbing (e.g. using real
480  * collections). In rare scenarios stubbing consecutive calls could be useful,
481  * though:
482  * <p>
483  *
484  * <pre class="code"><code class="java">
485  * when(mock.someMethod("some arg"))
486  *   .thenThrow(new RuntimeException())
487  *   .thenReturn("foo");
488  *
489  * //First call: throws runtime exception:
490  * mock.someMethod("some arg");
491  *
492  * //Second call: prints "foo"
493  * System.out.println(mock.someMethod("some arg"));
494  *
495  * //Any consecutive call: prints "foo" as well (last stubbing wins).
496  * System.out.println(mock.someMethod("some arg"));
497  * </code></pre>
498  *
499  * Alternative, shorter version of consecutive stubbing:
500  *
501  * <pre class="code"><code class="java">
502  * when(mock.someMethod("some arg"))
503  *   .thenReturn("one", "two", "three");
504  * </code></pre>
505  *
506  * <strong>Warning</strong> : if instead of chaining {@code .thenReturn()} calls, multiple stubbing with the same matchers or arguments
507  * is used, then each stubbing will override the previous one:
508  *
509  * <pre class="code"><code class="java">
510  * //All mock.someMethod("some arg") calls will return "two"
511  * when(mock.someMethod("some arg"))
512  *   .thenReturn("one")
513  * when(mock.someMethod("some arg"))
514  *   .thenReturn("two")
515  * </code></pre>
516  *
517  *
518  *
519  * <h3 id="11">11. <a class="meaningful_link" href="#answer_stubs" name="answer_stubs">Stubbing with callbacks</a></h3>
520  *
521  * Allows stubbing with generic {@link Answer} interface.
522  * <p>
523  * Yet another controversial feature which was not included in Mockito
524  * originally. We recommend simply stubbing with <code>thenReturn()</code> or
525  * <code>thenThrow()</code>, which should be enough to test/test-drive
526  * any clean & simple code. However, if you do have a need to stub with the generic Answer interface, here is an example:
527  *
528  * <pre class="code"><code class="java">
529  * when(mock.someMethod(anyString())).thenAnswer(
530  *     new Answer() {
531  *         public Object answer(InvocationOnMock invocation) {
532  *             Object[] args = invocation.getArguments();
533  *             Object mock = invocation.getMock();
534  *             return "called with arguments: " + Arrays.toString(args);
535  *         }
536  * });
537  *
538  * //Following prints "called with arguments: [foo]"
539  * System.out.println(mock.someMethod("foo"));
540  * </code></pre>
541  *
542  *
543  *
544  *
545  * <h3 id="12">12. <a class="meaningful_link" href="#do_family_methods_stubs" name="do_family_methods_stubs"><code>doReturn()</code>|<code>doThrow()</code>|
546  * <code>doAnswer()</code>|<code>doNothing()</code>|<code>doCallRealMethod()</code> family of methods</a></h3>
547  *
548  * Stubbing void methods requires a different approach from {@link Mockito#when(Object)} because the compiler does not
549  * like void methods inside brackets...
550  * <p>
551  * Use <code>doThrow()</code> when you want to stub a void method with an exception:
552  * <pre class="code"><code class="java">
553  *   doThrow(new RuntimeException()).when(mockedList).clear();
554  *
555  *   //following throws RuntimeException:
556  *   mockedList.clear();
557  * </code></pre>
558  * </p>
559  *
560  * <p>
561  * You can use <code>doThrow()</code>, <code>doAnswer()</code>, <code>doNothing()</code>, <code>doReturn()</code>
562  * and <code>doCallRealMethod()</code> in place of the corresponding call with <code>when()</code>, for any method.
563  * It is necessary when you
564  * <ul>
565  *     <li>stub void methods</li>
566  *     <li>stub methods on spy objects (see below)</li>
567  *     <li>stub the same method more than once, to change the behaviour of a mock in the middle of a test.</li>
568  * </ul>
569  * but you may prefer to use these methods in place of the alternative with <code>when()</code>, for all of your stubbing calls.
570  * <p>
571  * Read more about these methods:
572  * <p>
573  * {@link Mockito#doReturn(Object)}
574  * <p>
575  * {@link Mockito#doThrow(Throwable...)}
576  * <p>
577  * {@link Mockito#doThrow(Class)}
578  * <p>
579  * {@link Mockito#doAnswer(Answer)}
580  * <p>
581  * {@link Mockito#doNothing()}
582  * <p>
583  * {@link Mockito#doCallRealMethod()}
584  *
585  *
586  *
587  *
588  * <h3 id="13">13. <a class="meaningful_link" href="#spy" name="spy">Spying on real objects</a></h3>
589  *
590  * You can create spies of real objects. When you use the spy then the <b>real</b> methods are called
591  * (unless a method was stubbed).
592  * <p>
593  * Real spies should be used <b>carefully and occasionally</b>, for example when dealing with legacy code.
594  *
595  * <p>
596  * Spying on real objects can be associated with "partial mocking" concept.
597  * <b>Before the release 1.8</b>, Mockito spies were not real partial mocks.
598  * The reason was we thought partial mock is a code smell.
599  * At some point we found legitimate use cases for partial mocks
600  * (3rd party interfaces, interim refactoring of legacy code, the full article is
601  * <a href="http://monkeyisland.pl/2009/01/13/subclass-and-override-vs-partial-mocking-vs-refactoring">here</a>)
602  * <p>
603  *
604  * <pre class="code"><code class="java">
605  *   List list = new LinkedList();
606  *   List spy = spy(list);
607  *
608  *   //optionally, you can stub out some methods:
609  *   when(spy.size()).thenReturn(100);
610  *
611  *   //using the spy calls <b>*real*</b> methods
612  *   spy.add("one");
613  *   spy.add("two");
614  *
615  *   //prints "one" - the first element of a list
616  *   System.out.println(spy.get(0));
617  *
618  *   //size() method was stubbed - 100 is printed
619  *   System.out.println(spy.size());
620  *
621  *   //optionally, you can verify
622  *   verify(spy).add("one");
623  *   verify(spy).add("two");
624  * </code></pre>
625  *
626  * <h4>Important gotcha on spying real objects!</h4>
627  * <ol>
628  * <li>Sometimes it's impossible or impractical to use {@link Mockito#when(Object)} for stubbing spies.
629  * Therefore when using spies please consider <code>doReturn</code>|<code>Answer</code>|<code>Throw()</code> family of
630  * methods for stubbing. Example:
631  *
632  * <pre class="code"><code class="java">
633  *   List list = new LinkedList();
634  *   List spy = spy(list);
635  *
636  *   //Impossible: real method is called so spy.get(0) throws IndexOutOfBoundsException (the list is yet empty)
637  *   when(spy.get(0)).thenReturn("foo");
638  *
639  *   //You have to use doReturn() for stubbing
640  *   doReturn("foo").when(spy).get(0);
641  * </code></pre>
642  * </li>
643  *
644  * <li>Mockito <b>*does not*</b> delegate calls to the passed real instance, instead it actually creates a copy of it.
645  * So if you keep the real instance and interact with it, don't expect the spied to be aware of those interaction
646  * and their effect on real instance state.
647  * The corollary is that when an <b>*unstubbed*</b> method is called <b>*on the spy*</b> but <b>*not on the real instance*</b>,
648  * you won't see any effects on the real instance.
649  * </li>
650  *
651  * <li>Watch out for final methods.
652  * Mockito doesn't mock final methods so the bottom line is: when you spy on real objects + you try to stub a final method = trouble.
653  * Also you won't be able to verify those method as well.
654  * </li>
655  * </ol>
656  *
657  *
658  *
659  *
660  * <h3 id="14">14. Changing <a class="meaningful_link" href="#defaultreturn" name="defaultreturn">default return values of unstubbed invocations</a> (Since 1.7)</h3>
661  *
662  * You can create a mock with specified strategy for its return values.
663  * It's quite an advanced feature and typically you don't need it to write decent tests.
664  * However, it can be helpful for working with <b>legacy systems</b>.
665  * <p>
666  * It is the default answer so it will be used <b>only when you don't</b> stub the method call.
667  *
668  * <pre class="code"><code class="java">
669  *   Foo mock = mock(Foo.class, Mockito.RETURNS_SMART_NULLS);
670  *   Foo mockTwo = mock(Foo.class, new YourOwnAnswer());
671  * </code></pre>
672  *
673  * <p>
674  * Read more about this interesting implementation of <i>Answer</i>: {@link Mockito#RETURNS_SMART_NULLS}
675  *
676  *
677  *
678  *
679  * <h3 id="15">15. <a class="meaningful_link" href="#captors" name="captors">Capturing arguments</a> for further assertions (Since 1.8.0)</h3>
680  *
681  * Mockito verifies argument values in natural java style: by using an <code>equals()</code> method.
682  * This is also the recommended way of matching arguments because it makes tests clean & simple.
683  * In some situations though, it is helpful to assert on certain arguments after the actual verification.
684  * For example:
685  * <pre class="code"><code class="java">
686  *   ArgumentCaptor&lt;Person&gt; argument = ArgumentCaptor.forClass(Person.class);
687  *   verify(mock).doSomething(argument.capture());
688  *   assertEquals("John", argument.getValue().getName());
689  * </code></pre>
690  *
691  * <b>Warning:</b> it is recommended to use ArgumentCaptor with verification <b>but not</b> with stubbing.
692  * Using ArgumentCaptor with stubbing may decrease test readability because captor is created outside of assert (aka verify or 'then') block.
693  * Also it may reduce defect localization because if stubbed method was not called then no argument is captured.
694  * <p>
695  * In a way ArgumentCaptor is related to custom argument matchers (see javadoc for {@link ArgumentMatcher} class).
696  * Both techniques can be used for making sure certain arguments where passed to mocks.
697  * However, ArgumentCaptor may be a better fit if:
698  * <ul>
699  * <li>custom argument matcher is not likely to be reused</li>
700  * <li>you just need it to assert on argument values to complete verification</li>
701  * </ul>
702  * Custom argument matchers via {@link ArgumentMatcher} are usually better for stubbing.
703  *
704  *
705  *
706  *
707  * <h3 id="16">16. <a class="meaningful_link" href="#partial_mocks" name="partial_mocks">Real partial mocks</a> (Since 1.8.0)</h3>
708  *
709  *  Finally, after many internal debates & discussions on the mailing list, partial mock support was added to Mockito.
710  *  Previously we considered partial mocks as code smells. However, we found a legitimate use case for partial mocks - more reading:
711  *  <a href="http://monkeyisland.pl/2009/01/13/subclass-and-override-vs-partial-mocking-vs-refactoring">here</a>
712  *  <p>
713  *  <b>Before release 1.8</b> <code>spy()</code> was not producing real partial mocks and it was confusing for some users.
714  *  Read more about spying: <a href="#13">here</a> or in javadoc for {@link Mockito#spy(Object)} method.
715  *  <p>
716  *  <pre class="code"><code class="java">
717  *    //you can create partial mock with spy() method:
718  *    List list = spy(new LinkedList());
719  *
720  *    //you can enable partial mock capabilities selectively on mocks:
721  *    Foo mock = mock(Foo.class);
722  *    //Be sure the real implementation is 'safe'.
723  *    //If real implementation throws exceptions or depends on specific state of the object then you're in trouble.
724  *    when(mock.someMethod()).thenCallRealMethod();
725  *  </code></pre>
726  *
727  * As usual you are going to read <b>the partial mock warning</b>:
728  * Object oriented programming is more less tackling complexity by dividing the complexity into separate, specific, SRPy objects.
729  * How does partial mock fit into this paradigm? Well, it just doesn't...
730  * Partial mock usually means that the complexity has been moved to a different method on the same object.
731  * In most cases, this is not the way you want to design your application.
732  * <p>
733  * However, there are rare cases when partial mocks come handy:
734  * dealing with code you cannot change easily (3rd party interfaces, interim refactoring of legacy code etc.)
735  * However, I wouldn't use partial mocks for new, test-driven & well-designed code.
736  *
737  *
738  *
739  *
740  * <h3 id="17">17. <a class="meaningful_link" href="#resetting_mocks" name="resetting_mocks">Resetting mocks</a> (Since 1.8.0)</h3>
741  *
742  * Smart Mockito users hardly use this feature because they know it could be a sign of poor tests.
743  * Normally, you don't need to reset your mocks, just create new mocks for each test method.
744  * <p>
745  * Instead of <code>reset()</code> please consider writing simple, small and focused test methods over lengthy, over-specified tests.
746  * <b>First potential code smell is <code>reset()</code> in the middle of the test method.</b> This probably means you're testing too much.
747  * Follow the whisper of your test methods: "Please keep us small & focused on single behavior".
748  * There are several threads about it on mockito mailing list.
749  * <p>
750  * The only reason we added <code>reset()</code> method is to
751  * make it possible to work with container-injected mocks.
752  * For more information see FAQ (<a href="https://github.com/mockito/mockito/wiki/FAQ">here</a>).
753  * <p>
754  * <b>Don't harm yourself.</b> <code>reset()</code> in the middle of the test method is a code smell (you're probably testing too much).
755  * <pre class="code"><code class="java">
756  *   List mock = mock(List.class);
757  *   when(mock.size()).thenReturn(10);
758  *   mock.add(1);
759  *
760  *   reset(mock);
761  *   //at this point the mock forgot any interactions & stubbing
762  * </code></pre>
763  *
764  *
765  *
766  *
767  * <h3 id="18">18. <a class="meaningful_link" href="#framework_validation" name="framework_validation">Troubleshooting & validating framework usage</a> (Since 1.8.0)</h3>
768  *
769  * First of all, in case of any trouble, I encourage you to read the Mockito FAQ:
770  * <a href="https://github.com/mockito/mockito/wiki/FAQ">https://github.com/mockito/mockito/wiki/FAQ</a>
771  * <p>
772  * In case of questions you may also post to mockito mailing list:
773  * <a href="http://groups.google.com/group/mockito">http://groups.google.com/group/mockito</a>
774  * <p>
775  * Next, you should know that Mockito validates if you use it correctly <b>all the time</b>.
776  * However, there's a gotcha so please read the javadoc for {@link Mockito#validateMockitoUsage()}
777  *
778  *
779  *
780  *
781  * <h3 id="19">19. <a class="meaningful_link" href="#bdd_mockito" name="bdd_mockito">Aliases for behavior driven development</a> (Since 1.8.0)</h3>
782  *
783  * Behavior Driven Development style of writing tests uses <b>//given //when //then</b> comments as fundamental parts of your test methods.
784  * This is exactly how we write our tests and we warmly encourage you to do so!
785  * <p>
786  * Start learning about BDD here: <a href="http://en.wikipedia.org/wiki/Behavior_Driven_Development">http://en.wikipedia.org/wiki/Behavior_Driven_Development</a>
787  * <p>
788  * The problem is that current stubbing api with canonical role of <b>when</b> word does not integrate nicely with <b>//given //when //then</b> comments.
789  * It's because stubbing belongs to <b>given</b> component of the test and not to the <b>when</b> component of the test.
790  * Hence {@link BDDMockito} class introduces an alias so that you stub method calls with {@link BDDMockito#given(Object)} method.
791  * Now it really nicely integrates with the <b>given</b> component of a BDD style test!
792  * <p>
793  * Here is how the test might look like:
794  * <pre class="code"><code class="java">
795  * import static org.mockito.BDDMockito.*;
796  *
797  * Seller seller = mock(Seller.class);
798  * Shop shop = new Shop(seller);
799  *
800  * public void shouldBuyBread() throws Exception {
801  *   //given
802  *   given(seller.askForBread()).willReturn(new Bread());
803  *
804  *   //when
805  *   Goods goods = shop.buyBread();
806  *
807  *   //then
808  *   assertThat(goods, containBread());
809  * }
810  * </code></pre>
811  *
812  *
813  *
814  *
815  * <h3 id="20">20. <a class="meaningful_link" href="#serializable_mocks" name="serializable_mocks">Serializable mocks</a> (Since 1.8.1)</h3>
816  *
817  * Mocks can be made serializable. With this feature you can use a mock in a place that requires dependencies to be serializable.
818  * <p>
819  * WARNING: This should be rarely used in unit testing.
820  * <p>
821  * The behaviour was implemented for a specific use case of a BDD spec that had an unreliable external dependency.  This
822  * was in a web environment and the objects from the external dependency were being serialized to pass between layers.
823  * <p>
824  * To create serializable mock use {@link MockSettings#serializable()}:
825  * <pre class="code"><code class="java">
826  *   List serializableMock = mock(List.class, withSettings().serializable());
827  * </code></pre>
828  * <p>
829  * The mock can be serialized assuming all the normal <a href='http://java.sun.com/j2se/1.5.0/docs/api/java/io/Serializable.html'>
830  * serialization requirements</a> are met by the class.
831  * <p>
832  * Making a real object spy serializable is a bit more effort as the spy(...) method does not have an overloaded version
833  * which accepts MockSettings. No worries, you will hardly ever use it.
834  *
835  * <pre class="code"><code class="java">
836  * List&lt;Object&gt; list = new ArrayList&lt;Object&gt;();
837  * List&lt;Object&gt; spy = mock(ArrayList.class, withSettings()
838  *                 .spiedInstance(list)
839  *                 .defaultAnswer(CALLS_REAL_METHODS)
840  *                 .serializable());
841  * </code></pre>
842  *
843  *
844  *
845  *
846  * <h3 id="21">21. New annotations: <a class="meaningful_link" href="#captor_annotation" name="captor_annotation"><code>&#064;Captor</code></a>,
847  * <a class="meaningful_link" href="#spy_annotation" name="spy_annotation"><code>&#064;Spy</code></a>,
848  * <a class="meaningful_link" href="#injectmocks_annotation" name="injectmocks_annotation"><code>&#064;InjectMocks</code></a> (Since 1.8.3)</h3>
849  *
850  * <p>
851  * Release 1.8.3 brings new annotations that may be helpful on occasion:
852  *
853  * <ul>
854  * <li>&#064;{@link Captor} simplifies creation of {@link ArgumentCaptor}
855  * - useful when the argument to capture is a nasty generic class and you want to avoid compiler warnings
856  * <li>&#064;{@link Spy} - you can use it instead {@link Mockito#spy(Object)}.
857  * <li>&#064;{@link InjectMocks} - injects mock or spy fields into tested object automatically.
858  * </ul>
859  *
860  * <p>
861  * Note that &#064;{@link InjectMocks} can also be used in combination with the &#064;{@link Spy} annotation, it means
862  * that Mockito will inject mocks into the partial mock under test. This complexity is another good reason why you
863  * should only use partial mocks as a last resort. See point 16 about partial mocks.
864  *
865  * <p>
866  * All new annotations are <b>*only*</b> processed on {@link MockitoAnnotations#initMocks(Object)}.
867  * Just like for &#064;{@link Mock} annotation you can use the built-in runner: {@link MockitoJUnitRunner} or rule:
868  * {@link MockitoRule}.
869  * <p>
870  *
871  *
872  *
873  *
874  * <h3 id="22">22. <a class="meaningful_link" href="#verification_timeout" name="verification_timeout">Verification with timeout</a> (Since 1.8.5)</h3>
875  * <p>
876  * Allows verifying with timeout. It causes a verify to wait for a specified period of time for a desired
877  * interaction rather than fails immediately if had not already happened. May be useful for testing in concurrent
878  * conditions.
879  * <p>
880  * This feature should be used rarely - figure out a better way of testing your multi-threaded system.
881  * <p>
882  * Not yet implemented to work with InOrder verification.
883  * <p>
884  * Examples:
885  * <p>
886  * <pre class="code"><code class="java">
887  *   //passes when someMethod() is called no later than within 100 ms
888  *   //exits immediately when verification is satisfied (e.g. may not wait full 100 ms)
889  *   verify(mock, timeout(100)).someMethod();
890  *   //above is an alias to:
891  *   verify(mock, timeout(100).times(1)).someMethod();
892  *
893  *   //passes as soon as someMethod() has been called 2 times under 100 ms
894  *   verify(mock, timeout(100).times(2)).someMethod();
895  *
896  *   //equivalent: this also passes as soon as someMethod() has been called 2 times under 100 ms
897  *   verify(mock, timeout(100).atLeast(2)).someMethod();
898  * </code></pre>
899  *
900  *
901  *
902  *
903  * <h3 id="23">23. <a class="meaningful_link" href="#automatic_instantiation" name="automatic_instantiation">Automatic instantiation of <code>&#064;Spies</code>,
904  * <code>&#064;InjectMocks</code></a> and <a class="meaningful_link" href="#constructor_injection" name="constructor_injection">constructor injection goodness</a> (Since 1.9.0)</h3>
905  *
906  * <p>
907  * Mockito will now try to instantiate &#064;{@link Spy} and will instantiate &#064;{@link InjectMocks} fields
908  * using <b>constructor</b> injection, <b>setter</b> injection, or <b>field</b> injection.
909  * <p>
910  * To take advantage of this feature you need to use {@link MockitoAnnotations#initMocks(Object)}, {@link MockitoJUnitRunner}
911  * or {@link MockitoRule}.
912  * <p>
913  * Read more about available tricks and the rules of injection in the javadoc for {@link InjectMocks}
914  * <pre class="code"><code class="java">
915  * //instead:
916  * &#064;Spy BeerDrinker drinker = new BeerDrinker();
917  * //you can write:
918  * &#064;Spy BeerDrinker drinker;
919  *
920  * //same applies to &#064;InjectMocks annotation:
921  * &#064;InjectMocks LocalPub;
922  * </code></pre>
923  *
924  *
925  *
926  *
927  * <h3 id="24">24. <a class="meaningful_link" href="#one_liner_stub" name="one_liner_stub">One-liner stubs</a> (Since 1.9.0)</h3>
928  * <p>
929  * Mockito will now allow you to create mocks when stubbing.
930  * Basically, it allows to create a stub in one line of code.
931  * This can be helpful to keep test code clean.
932  * For example, some boring stub can be created & stubbed at field initialization in a test:
933  * <pre class="code"><code class="java">
934  * public class CarTest {
935  *   Car boringStubbedCar = when(mock(Car.class).shiftGear()).thenThrow(EngineNotStarted.class).getMock();
936  *
937  *   &#064;Test public void should... {}
938  * </code></pre>
939  *
940  *
941  *
942  *
943  * <h3 id="25">25. <a class="meaningful_link" href="#ignore_stubs_verification" name="ignore_stubs_verification">Verification ignoring stubs</a> (Since 1.9.0)</h3>
944  * <p>
945  * Mockito will now allow to ignore stubbing for the sake of verification.
946  * Sometimes useful when coupled with <code>verifyNoMoreInteractions()</code> or verification <code>inOrder()</code>.
947  * Helps avoiding redundant verification of stubbed calls - typically we're not interested in verifying stubs.
948  * <p>
949  * <b>Warning</b>, <code>ignoreStubs()</code> might lead to overuse of verifyNoMoreInteractions(ignoreStubs(...));
950  * Bear in mind that Mockito does not recommend bombarding every test with <code>verifyNoMoreInteractions()</code>
951  * for the reasons outlined in javadoc for {@link Mockito#verifyNoMoreInteractions(Object...)}
952  * <p>Some examples:
953  * <pre class="code"><code class="java">
954  * verify(mock).foo();
955  * verify(mockTwo).bar();
956  *
957  * //ignores all stubbed methods:
958  * verifyNoMoreInteractions(ignoreStubs(mock, mockTwo));
959  *
960  * //creates InOrder that will ignore stubbed
961  * InOrder inOrder = inOrder(ignoreStubs(mock, mockTwo));
962  * inOrder.verify(mock).foo();
963  * inOrder.verify(mockTwo).bar();
964  * inOrder.verifyNoMoreInteractions();
965  * </code></pre>
966  * <p>
967  * Advanced examples and more details can be found in javadoc for {@link Mockito#ignoreStubs(Object...)}
968  *
969  *
970  *
971  *
972  * <h3 id="26">26. <a class="meaningful_link" href="#mocking_details" name="mocking_details">Mocking details</a> (Improved in 2.2.x)</h3>
973  * <p>
974  *
975  * Mockito offers API to inspect the details of a mock object.
976  * This API is useful for advanced users and mocking framework integrators.
977  *
978  * <pre class="code"><code class="java">
979  *   //To identify whether a particular object is a mock or a spy:
980  *   Mockito.mockingDetails(someObject).isMock();
981  *   Mockito.mockingDetails(someObject).isSpy();
982  *
983  *   //Getting details like type to mock or default answer:
984  *   MockingDetails details = mockingDetails(mock);
985  *   details.getMockCreationSettings().getTypeToMock();
986  *   details.getMockCreationSettings().getDefaultAnswer();
987  *
988  *   //Getting invocations and stubbings of the mock:
989  *   MockingDetails details = mockingDetails(mock);
990  *   details.getInvocations();
991  *   details.getStubbings();
992  *
993  *   //Printing all interactions (including stubbing, unused stubs)
994  *   System.out.println(mockingDetails(mock).printInvocations());
995  * </code></pre>
996  *
997  * For more information see javadoc for {@link MockingDetails}.
998  *
999  * <h3 id="27">27. <a class="meaningful_link" href="#delegating_call_to_real_instance" name="delegating_call_to_real_instance">Delegate calls to real instance</a> (Since 1.9.5)</h3>
1000  *
1001  * <p>Useful for spies or partial mocks of objects <strong>that are difficult to mock or spy</strong> using the usual spy API.
1002  * Since Mockito 1.10.11, the delegate may or may not be of the same type as the mock.
1003  * If the type is different, a matching method needs to be found on delegate type otherwise an exception is thrown.
1004  *
1005  * Possible use cases for this feature:
1006  * <ul>
1007  *     <li>Final classes but with an interface</li>
1008  *     <li>Already custom proxied object</li>
1009  *     <li>Special objects with a finalize method, i.e. to avoid executing it 2 times</li>
1010  * </ul>
1011  *
1012  * <p>The difference with the regular spy:
1013  * <ul>
1014  *   <li>
1015  *     The regular spy ({@link #spy(Object)}) contains <strong>all</strong> state from the spied instance
1016  *     and the methods are invoked on the spy. The spied instance is only used at mock creation to copy the state from.
1017  *     If you call a method on a regular spy and it internally calls other methods on this spy, those calls are remembered
1018  *     for verifications, and they can be effectively stubbed.
1019  *   </li>
1020  *   <li>
1021  *     The mock that delegates simply delegates all methods to the delegate.
1022  *     The delegate is used all the time as methods are delegated onto it.
1023  *     If you call a method on a mock that delegates and it internally calls other methods on this mock,
1024  *     those calls are <strong>not</strong> remembered for verifications, stubbing does not have effect on them, too.
1025  *     Mock that delegates is less powerful than the regular spy but it is useful when the regular spy cannot be created.
1026  *   </li>
1027  * </ul>
1028  *
1029  * <p>
1030  * See more information in docs for {@link AdditionalAnswers#delegatesTo(Object)}.
1031  *
1032  *
1033  *
1034  *
1035  * <h3 id="28">28. <a class="meaningful_link" href="#mock_maker_plugin" name="mock_maker_plugin"><code>MockMaker</code> API</a> (Since 1.9.5)</h3>
1036  * <p>Driven by requirements and patches from Google Android guys Mockito now offers an extension point
1037  *   that allows replacing the proxy generation engine. By default, Mockito uses <a href="https://github.com/raphw/byte-buddy">Byte Buddy</a>
1038  *   to create dynamic proxies.
1039  * <p>The extension point is for advanced users that want to extend Mockito. For example, it is now possible
1040  *   to use Mockito for Android testing with a help of <a href="https://github.com/crittercism/dexmaker">dexmaker</a>.
1041  * <p>For more details, motivations and examples please refer to
1042  * the docs for {@link org.mockito.plugins.MockMaker}.
1043  *
1044  *
1045  *
1046  *
1047  * <h3 id="29">29. <a class="meaningful_link" href="#BDD_behavior_verification" name="BDD_behavior_verification">BDD style verification</a> (Since 1.10.0)</h3>
1048  *
1049  * Enables Behavior Driven Development (BDD) style verification by starting verification with the BDD <b>then</b> keyword.
1050  *
1051  * <pre class="code"><code class="java">
1052  * given(dog.bark()).willReturn(2);
1053  *
1054  * // when
1055  * ...
1056  *
1057  * then(person).should(times(2)).ride(bike);
1058  * </code></pre>
1059  *
1060  * For more information and an example see {@link BDDMockito#then(Object)}
1061  *
1062  *
1063  *
1064  *
1065  * <h3 id="30">30. <a class="meaningful_link" href="#spying_abstract_classes" name="spying_abstract_classes">Spying or mocking abstract classes (Since 1.10.12, further enhanced in 2.7.13 and 2.7.14)</a></h3>
1066  *
1067  * It is now possible to conveniently spy on abstract classes. Note that overusing spies hints at code design smells (see {@link #spy(Object)}).
1068  * <p>
1069  * Previously, spying was only possible on instances of objects.
1070  * New API makes it possible to use constructor when creating an instance of the mock.
1071  * This is particularly useful for mocking abstract classes because the user is no longer required to provide an instance of the abstract class.
1072  * At the moment, only parameter-less constructor is supported, let us know if it is not enough.
1073  *
1074  * <pre class="code"><code class="java">
1075  * //convenience API, new overloaded spy() method:
1076  * SomeAbstract spy = spy(SomeAbstract.class);
1077  *
1078  * //Mocking abstract methods, spying default methods of an interface (only available since 2.7.13)
1079  * Function<Foo, Bar> function = spy(Function.class);
1080  *
1081  * //Robust API, via settings builder:
1082  * OtherAbstract spy = mock(OtherAbstract.class, withSettings()
1083  *    .useConstructor().defaultAnswer(CALLS_REAL_METHODS));
1084  *
1085  * //Mocking an abstract class with constructor arguments (only available since 2.7.14)
1086  * SomeAbstract spy = mock(SomeAbstract.class, withSettings()
1087  *   .useConstructor("arg1", 123).defaultAnswer(CALLS_REAL_METHODS));
1088  *
1089  * //Mocking a non-static inner abstract class:
1090  * InnerAbstract spy = mock(InnerAbstract.class, withSettings()
1091  *    .useConstructor().outerInstance(outerInstance).defaultAnswer(CALLS_REAL_METHODS));
1092  * </code></pre>
1093  *
1094  * For more information please see {@link MockSettings#useConstructor(Object...)}.
1095  *
1096  *
1097  *
1098  *
1099  * <h3 id="31">31. <a class="meaningful_link" href="#serilization_across_classloader" name="serilization_across_classloader">Mockito mocks can be <em>serialized</em> / <em>deserialized</em> across classloaders (Since 1.10.0)</a></h3>
1100  *
1101  * Mockito introduces serialization across classloader.
1102  *
1103  * Like with any other form of serialization, all types in the mock hierarchy have to serializable, inclusing answers.
1104  * As this serialization mode require considerably more work, this is an opt-in setting.
1105  *
1106  * <pre class="code"><code class="java">
1107  * // use regular serialization
1108  * mock(Book.class, withSettings().serializable());
1109  *
1110  * // use serialization across classloaders
1111  * mock(Book.class, withSettings().serializable(ACROSS_CLASSLOADERS));
1112  * </code></pre>
1113  *
1114  * For more details see {@link MockSettings#serializable(SerializableMode)}.
1115  *
1116  *
1117  *
1118  *
1119  * <h3 id="32">32. <a class="meaningful_link" href="#better_generic_support_with_deep_stubs" name="better_generic_support_with_deep_stubs">Better generic support with deep stubs (Since 1.10.0)</a></h3>
1120  *
1121  * Deep stubbing has been improved to find generic information if available in the class.
1122  * That means that classes like this can be used without having to mock the behavior.
1123  *
1124  * <pre class="code"><code class="java">
1125  * class Lines extends List&lt;Line&gt; {
1126  *     // ...
1127  * }
1128  *
1129  * lines = mock(Lines.class, RETURNS_DEEP_STUBS);
1130  *
1131  * // Now Mockito understand this is not an Object but a Line
1132  * Line line = lines.iterator().next();
1133  * </code></pre>
1134  *
1135  * Please note that in most scenarios a mock returning a mock is wrong.
1136  *
1137  *
1138  *
1139  *
1140  * <h3 id="33">33. <a class="meaningful_link" href="#mockito_junit_rule" name="mockito_junit_rule">Mockito JUnit rule (Since 1.10.17)</a></h3>
1141  *
1142  * Mockito now offers a JUnit rule. Until now in JUnit there were two ways to initialize fields annotated by Mockito annotations
1143  * such as <code>&#064;{@link Mock}</code>, <code>&#064;{@link Spy}</code>, <code>&#064;{@link InjectMocks}</code>, etc.
1144  *
1145  * <ul>
1146  *     <li>Annotating the JUnit test class with a <code>&#064;{@link org.junit.runner.RunWith}({@link MockitoJUnitRunner}.class)</code></li>
1147  *     <li>Invoking <code>{@link MockitoAnnotations#initMocks(Object)}</code> in the <code>&#064;{@link org.junit.Before}</code> method</li>
1148  * </ul>
1149  *
1150  * Now you can choose to use a rule :
1151  *
1152  * <pre class="code"><code class="java">
1153  * &#064;RunWith(YetAnotherRunner.class)
1154  * public class TheTest {
1155  *     &#064;Rule public MockitoRule mockito = MockitoJUnit.rule();
1156  *     // ...
1157  * }
1158  * </code></pre>
1159  *
1160  * For more information see {@link MockitoJUnit#rule()}.
1161  *
1162  *
1163  *
1164  *
1165  * <h3 id="34">34. <a class="meaningful_link" href="#plugin_switch" name="plugin_switch">Switch <em>on</em> or <em>off</em> plugins (Since 1.10.15)</a></h3>
1166  *
1167  * An incubating feature made it's way in mockito that will allow to toggle a mockito-plugin.
1168  *
1169  * More information here {@link org.mockito.plugins.PluginSwitch}.
1170  *
1171  *
1172  * <h3 id="35">35. <a class="meaningful_link" href="#Custom_verification_failure_message" name="Custom_verification_failure_message">Custom verification failure message</a> (Since 2.1.0)</h3>
1173  * <p>
1174  * Allows specifying a custom message to be printed if verification fails.
1175  * <p>
1176  * Examples:
1177  * <p>
1178  * <pre class="code"><code class="java">
1179  *
1180  * // will print a custom message on verification failure
1181  * verify(mock, description("This will print on failure")).someMethod();
1182  *
1183  * // will work with any verification mode
1184  * verify(mock, times(2).description("someMethod should be called twice")).someMethod();
1185  * </code></pre>
1186  *
1187  * <h3 id="36">36. <a class="meaningful_link" href="#Java_8_Lambda_Matching" name="Java_8_Lambda_Matching">Java 8 Lambda Matcher Support</a> (Since 2.1.0)</h3>
1188  * <p>
1189  * You can use Java 8 lambda expressions with {@link ArgumentMatcher} to reduce the dependency on {@link ArgumentCaptor}.
1190  * If you need to verify that the input to a function call on a mock was correct, then you would normally
1191  * use the {@link ArgumentCaptor} to find the operands used and then do subsequent assertions on them. While
1192  * for complex examples this can be useful, it's also long-winded.<p>
1193  * Writing a lambda to express the match is quite easy. The argument to your function, when used in conjunction
1194  * with argThat, will be passed to the ArgumentMatcher as a strongly typed object, so it is possible
1195  * to do anything with it.
1196  * <p>
1197  * Examples:
1198  * <p>
1199  * <pre class="code"><code class="java">
1200  *
1201  * // verify a list only had strings of a certain length added to it
1202  * // note - this will only compile under Java 8
1203  * verify(list, times(2)).add(argThat(string -> string.length() < 5));
1204  *
1205  * // Java 7 equivalent - not as neat
1206  * verify(list, times(2)).add(argThat(new ArgumentMatcher<String>(){
1207  *     public boolean matches(String arg) {
1208  *         return arg.length() < 5;
1209  *     }
1210  * }));
1211  *
1212  * // more complex Java 8 example - where you can specify complex verification behaviour functionally
1213  * verify(target, times(1)).receiveComplexObject(argThat(obj -> obj.getSubObject().get(0).equals("expected")));
1214  *
1215  * // this can also be used when defining the behaviour of a mock under different inputs
1216  * // in this case if the input list was fewer than 3 items the mock returns null
1217  * when(mock.someMethod(argThat(list -> list.size()<3))).thenReturn(null);
1218  * </code></pre>
1219  *
1220  * <h3 id="37">37. <a class="meaningful_link" href="#Java_8_Custom_Answers" name="Java_8_Custom_Answers">Java 8 Custom Answer Support</a> (Since 2.1.0)</h3>
1221  * <p>
1222  * As the {@link Answer} interface has just one method it is already possible to implement it in Java 8 using
1223  * a lambda expression for very simple situations. The more you need to use the parameters of the method call,
1224  * the more you need to typecast the arguments from {@link org.mockito.invocation.InvocationOnMock}.
1225  *
1226  * <p>
1227  * Examples:
1228  * <p>
1229  * <pre class="code"><code class="java">
1230  * // answer by returning 12 every time
1231  * doAnswer(invocation -> 12).when(mock).doSomething();
1232  *
1233  * // answer by using one of the parameters - converting into the right
1234  * // type as your go - in this case, returning the length of the second string parameter
1235  * // as the answer. This gets long-winded quickly, with casting of parameters.
1236  * doAnswer(invocation -> ((String)invocation.getArgument(1)).length())
1237  *     .when(mock).doSomething(anyString(), anyString(), anyString());
1238  * </code></pre>
1239  *
1240  * For convenience it is possible to write custom answers/actions, which use the parameters to the method call,
1241  * as Java 8 lambdas. Even in Java 7 and lower these custom answers based on a typed interface can reduce boilerplate.
1242  * In particular, this approach will make it easier to test functions which use callbacks.
1243  *
1244  * The methods {@link AdditionalAnswers#answer(Answer1) answer} and {@link AdditionalAnswers#answerVoid(VoidAnswer1) answerVoid}
1245  * can be used to create the answer. They rely on the related answer interfaces in {@link org.mockito.stubbing} that
1246  * support answers up to 5 parameters.
1247  *
1248  * <p>
1249  * Examples:
1250  * <p>
1251  * <pre class="code"><code class="java">
1252  *
1253  * // Example interface to be mocked has a function like:
1254  * void execute(String operand, Callback callback);
1255  *
1256  * // the example callback has a function and the class under test
1257  * // will depend on the callback being invoked
1258  * void receive(String item);
1259  *
1260  * // Java 8 - style 1
1261  * doAnswer(AdditionalAnswers.<String,Callback>answerVoid((operand, callback) -> callback.receive("dummy"))
1262  *     .when(mock).execute(anyString(), any(Callback.class));
1263  *
1264  * // Java 8 - style 2 - assuming static import of AdditionalAnswers
1265  * doAnswer(answerVoid((String operand, Callback callback) -> callback.receive("dummy"))
1266  *     .when(mock).execute(anyString(), any(Callback.class));
1267  *
1268  * // Java 8 - style 3 - where mocking function to is a static member of test class
1269  * private static void dummyCallbackImpl(String operation, Callback callback) {
1270  *     callback.receive("dummy");
1271  * }
1272  *
1273  * doAnswer(answerVoid(TestClass::dummyCallbackImpl)
1274  *     .when(mock).execute(anyString(), any(Callback.class));
1275  *
1276  * // Java 7
1277  * doAnswer(answerVoid(new VoidAnswer2<String, Callback>() {
1278  *     public void answer(String operation, Callback callback) {
1279  *         callback.receive("dummy");
1280  *     }})).when(mock).execute(anyString(), any(Callback.class));
1281  *
1282  * // returning a value is possible with the answer() function
1283  * // and the non-void version of the functional interfaces
1284  * // so if the mock interface had a method like
1285  * boolean isSameString(String input1, String input2);
1286  *
1287  * // this could be mocked
1288  * // Java 8
1289  * doAnswer(AdditionalAnswers.<Boolean,String,String>answer((input1, input2) -> input1.equals(input2))))
1290  *     .when(mock).execute(anyString(), anyString());
1291  *
1292  * // Java 7
1293  * doAnswer(answer(new Answer2<String, String, String>() {
1294  *     public String answer(String input1, String input2) {
1295  *         return input1 + input2;
1296  *     }})).when(mock).execute(anyString(), anyString());
1297  * </code></pre>
1298  *
1299  * <h3 id="38">38. <a class="meaningful_link" href="#Meta_Data_And_Generics" name="Meta_Data_And_Generics">Meta data and generic type retention</a> (Since 2.1.0)</h3>
1300  *
1301  * <p>
1302  * Mockito now preserves annotations on mocked methods and types as well as generic meta data. Previously, a mock type did not preserve
1303  * annotations on types unless they were explicitly inherited and never retained annotations on methods. As a consequence, the following
1304  * conditions now hold true:
1305  *
1306  * <pre class="code"><code class="java">
1307  * {@literal @}{@code MyAnnotation
1308  *  class Foo {
1309  *    List<String> bar() { ... }
1310  *  }
1311  *
1312  *  Class<?> mockType = mock(Foo.class).getClass();
1313  *  assert mockType.isAnnotationPresent(MyAnnotation.class);
1314  *  assert mockType.getDeclaredMethod("bar").getGenericReturnType() instanceof ParameterizedType;
1315  * }</code></pre>
1316  *
1317  * <p>
1318  * When using Java 8, Mockito now also preserves type annotations. This is default behavior and might not hold <a href="#28">if an
1319  * alternative {@link org.mockito.plugins.MockMaker} is used</a>.
1320  *
1321  * <h3 id="39">39. <a class="meaningful_link" href="#Mocking_Final" name="Mocking_Final">Mocking final types, enums and final methods</a> (Since 2.1.0)</h3>
1322  *
1323  * Mockito now offers an {@link Incubating}, optional support for mocking final classes and methods.
1324  * This is a fantastic improvement that demonstrates Mockito's everlasting quest for improving testing experience.
1325  * Our ambition is that Mockito "just works" with final classes and methods.
1326  * Previously they were considered <em>unmockable</em>, preventing the user from mocking.
1327  * We already started discussing how to make this feature enabled by default.
1328  * Currently, the feature is still optional as we wait for more feedback from the community.
1329  *
1330  * <p>
1331  * This alternative mock maker which uses
1332  * a combination of both Java instrumentation API and sub-classing rather than creating a new class to represent
1333  * a mock. This way, it becomes possible to mock final types and methods.
1334  *
1335  * <p>
1336  * This mock maker is <strong>turned off by default</strong> because it is based on completely different mocking mechanism
1337  * that requires more feedback from the community. It can be activated explicitly by the mockito extension mechanism,
1338  * just create in the classpath a file <code>/mockito-extensions/org.mockito.plugins.MockMaker</code>
1339  * containing the value <code>mock-maker-inline</code>.
1340  *
1341  * <p>
1342  * As a convenience, the Mockito team provides an artifact where this mock maker is preconfigured. Instead of using the
1343  * <i>mockito-core</i> artifact, include the <i>mockito-inline</i> artifact in your project. Note that this artifact is
1344  * likely to be discontinued once mocking of final classes and methods gets integrated into the default mock maker.
1345  *
1346  * <p>
1347  * Some noteworthy notes about this mock maker:
1348  * <ul>
1349  *     <li>Mocking final types and enums is incompatible with mock settings like :
1350  *     <ul>
1351  *         <li>explicitly serialization support <code>withSettings().serializable()</code></li>
1352  *         <li>extra-interfaces <code>withSettings().extraInterfaces()</code></li>
1353  *     </ul>
1354  *     </li>
1355  *     <li>Some methods cannot be mocked
1356  *         <ul>
1357  *              <li>Package-visible methods of <code>java.*</code></li>
1358  *              <li><code>native</code> methods</li>
1359  *         </ul>
1360  *     </li>
1361  *     <li>This mock maker has been designed around Java Agent runtime attachment ; this require a compatible JVM,
1362  *     that is part of the JDK (or Java 9 VM). When running on a non-JDK VM prior to Java 9, it is however possible to
1363  *     manually add the <a href="http://bytebuddy.net">Byte Buddy Java agent jar</a> using the <code>-javaagent</code>
1364  *     parameter upon starting the JVM.
1365  *     </li>
1366  * </ul>
1367  *
1368  * <p>
1369  * If you are interested in more details of this feature please read the javadoc of
1370  * <code>org.mockito.internal.creation.bytebuddy.InlineByteBuddyMockMaker</code>
1371  *
1372  * <h3 id="40">40. <a class="meaningful_link" href="#strict_mockito" name="strict_mockito">
1373  *     Improved productivity and cleaner tests with "stricter" Mockito</a> (Since 2.+)</h3>
1374  *
1375  * To quickly find out how "stricter" Mockito can make you more productive and get your tests cleaner, see:
1376  * <ul>
1377  *     <li>Strict stubbing with JUnit Rules - {@link MockitoRule#strictness(Strictness)} with {@link Strictness#STRICT_STUBS}</li>
1378  *     <li>Strict stubbing with JUnit Runner - {@link MockitoJUnitRunner.StrictStubs}</li>
1379  *     <li>Strict stubbing if you cannot use runner/rule (like TestNG) - {@link MockitoSession}</li>
1380  *     <li>Unnecessary stubbing detection with {@link MockitoJUnitRunner}</li>
1381  *     <li>Stubbing argument mismatch warnings, documented in {@link MockitoHint}</li>
1382  * </ul>
1383  *
1384  * Mockito is a "loose" mocking framework by default.
1385  * Mocks can be interacted with without setting any expectations beforehand.
1386  * This is intentional and it improves the quality of tests by forcing users to be explicit about what they want to stub / verify.
1387  * It is also very intuitive, easy to use and blends nicely with "given", "when", "then" template of clean test code.
1388  * This is also different from the classic mocking frameworks of the past, they were "strict" by default.
1389  * <p>
1390  * Being "loose" by default makes Mockito tests harder to debug at times.
1391  * There are scenarios where misconfigured stubbing (like using a wrong argument) forces the user to run the test with a debugger.
1392  * Ideally, tests failures are immediately obvious and don't require debugger to identify the root cause.
1393  * Starting with version 2.1 Mockito has been getting new features that nudge the framework towards "strictness".
1394  * We want Mockito to offer fantastic debuggability while not losing its core mocking style, optimized for
1395  * intuitiveness, explicitness and clean test code.
1396  * <p>
1397  * Help Mockito! Try the new features, give us feedback, join the discussion about Mockito strictness at GitHub
1398  * <a href="https://github.com/mockito/mockito/issues/769">issue 769</a>.
1399  *
1400  * <h3 id="41">41. <a class="meaningful_link" href="#framework_integrations_api" name="framework_integrations_api">
1401  *      Advanced public API for framework integrations (Since 2.10.+)</a></h3>
1402  *
1403  * In Summer 2017 we decided that Mockito
1404  * <a href="https://www.linkedin.com/pulse/mockito-vs-powermock-opinionated-dogmatic-static-mocking-faber">
1405  * should offer better API
1406  * </a>
1407  * for advanced framework integrations.
1408  * The new API is not intended for users who want to write unit tests.
1409  * It is intended for other test tools and mocking frameworks that need to extend or wrap Mockito with some custom logic.
1410  * During the design and implementation process (<a href="https://github.com/mockito/mockito/issues/1110">issue 1110</a>)
1411  * we have developed and changed following public API elements:
1412  * <ul>
1413  *     <li>New {@link MockitoPlugins} -
1414  *      Enables framework integrators to get access to default Mockito plugins.
1415  *      Useful when one needs to implement custom plugin such as {@link MockMaker}
1416  *      and delegate some behavior to the default Mockito implementation.
1417  *     </li>
1418  *     <li>New {@link MockSettings#build(Class)} -
1419  *      Creates immutable view of mock settings used later by Mockito.
1420  *      Useful for creating invocations with {@link InvocationFactory} or when implementing custom {@link MockHandler}.
1421  *     </li>
1422  *     <li>New {@link MockingDetails#getMockHandler()} -
1423  *      Other frameworks may use the mock handler to programmatically simulate invocations on mock objects.
1424  *     </li>
1425  *     <li>New {@link MockHandler#getMockSettings()} -
1426  *      Useful to get hold of the setting the mock object was created with.
1427  *     </li>
1428  *     <li>New {@link InvocationFactory} -
1429  *      Provides means to create instances of {@link Invocation} objects.
1430  *      Useful for framework integrations that need to programmatically simulate method calls on mock objects.
1431  *     </li>
1432  *     <li>New {@link MockHandler#getInvocationContainer()} -
1433  *      Provides access to invocation container object which has no methods (marker interface).
1434  *      Container is needed to hide the internal implementation and avoid leaking it to the public API.
1435  *     </li>
1436  *     <li>Changed {@link Stubbing} -
1437  *      it now extends {@link Answer} interface.
1438  *      It is backwards compatible because Stubbing interface is not extensible (see {@link NotExtensible}).
1439  *      The change should be seamless to our users.
1440  *     </li>
1441  *     <li>Deprecated {@link InternalMockHandler} -
1442  *       In order to accommodate API changes we needed to deprecate this interface.
1443  *       The interface was always documented as internal, we don't have evidence it was used by the community.
1444  *       The deprecation should be completely seamless for our users.
1445  *     </li>
1446  *     <li>{@link NotExtensible} -
1447  *       Public annotation that indicates to the user that she should not provide custom implementations of given type.
1448  *       Helps framework integrators and our users understand how to use Mockito API safely.
1449  *     </li>
1450  * </ul>
1451  * Do you have feedback? Please leave comment in <a href="https://github.com/mockito/mockito/issues/1110">issue 1110</a>.
1452  *
1453  * <h3 id="42">42. <a class="meaningful_link" href="#verifiation_started_listener" name="verifiation_started_listener">
1454  *       New API for integrations: listening on verification start events (Since 2.11.+)</a></h3>
1455  *
1456  * Framework integrations such as <a href="https://projects.spring.io/spring-boot">Spring Boot</a> needs public API to tackle double-proxy use case
1457  * (<a href="https://github.com/mockito/mockito/issues/1191">issue 1191</a>).
1458  * We added:
1459  * <ul>
1460  *     <li>New {@link VerificationStartedListener} and {@link VerificationStartedEvent}
1461  *      enable framework integrators to replace the mock object for verification.
1462  *      The main driving use case is <a href="https://projects.spring.io/spring-boot/">Spring Boot</a> integration.
1463  *      For details see Javadoc for {@link VerificationStartedListener}.
1464  *     </li>
1465  *     <li>New public method {@link MockSettings#verificationStartedListeners(VerificationStartedListener...)}
1466  *     allows to supply verification started listeners at mock creation time.
1467  *     </li>
1468  *     <li>New handy method {@link MockingDetails#getMock()} was added to make the {@code MockingDetails} API more complete.
1469  *     We found this method useful during the implementation.
1470  *     </li>
1471  * </ul>
1472  *
1473  * <h3 id="43">43. <a class="meaningful_link" href="#mockito_session_testing_frameworks" name="mockito_session_testing_frameworks">
1474  *       New API for integrations: <code>MockitoSession</code> is usable by testing frameworks (Since 2.15.+)</a></h3>
1475  *
1476  * <p>{@link MockitoSessionBuilder} and {@link MockitoSession} were enhanced to enable reuse by testing framework
1477  * integrations (e.g. {@link MockitoRule} for JUnit):</p>
1478  * <ul>
1479  *     <li>{@link MockitoSessionBuilder#initMocks(Object...)} allows to pass in multiple test class instances for
1480  *      initialization of fields annotated with Mockito annotations like {@link org.mockito.Mock}.
1481  *      This method is useful for advanced framework integrations (e.g. JUnit Jupiter), when a test uses multiple,
1482  *      e.g. nested, test class instances.
1483  *     </li>
1484  *     <li>{@link MockitoSessionBuilder#name(String)} allows to pass a name from the testing framework to the
1485  *      {@link MockitoSession} that will be used for printing warnings when {@link Strictness#WARN} is used.
1486  *     </li>
1487  *     <li>{@link MockitoSessionBuilder#logger(MockitoSessionLogger)} makes it possible to customize the logger used
1488  *      for hints/warnings produced when finishing mocking (useful for testing and to connect reporting capabilities
1489  *      provided by testing frameworks such as JUnit Jupiter).
1490  *     </li>
1491  *     <li>{@link MockitoSession#setStrictness(Strictness)} allows to change the strictness of a {@link MockitoSession}
1492  *      for one-off scenarios, e.g. it enables configuring a default strictness for all tests in a class but makes it
1493  *      possible to change the strictness for a single or a few tests.
1494  *     </li>
1495  *     <li>{@link MockitoSession#finishMocking(Throwable)} was added to avoid confusion that may arise because
1496  *      there are multiple competing failures. It will disable certain checks when the supplied <em>failure</em>
1497  *      is not {@code null}.
1498  *     </li>
1499  * </ul>
1500  *
1501  * <h3 id="44">44. <a class="meaningful_link" href="#mockito_instantiator_provider_deprecation" name="mockito_instantiator_provider_deprecation">
1502  *       Deprecated <code>org.mockito.plugins.InstantiatorProvider</code> as it was leaking internal API. it was
1503  *       replaced by <code>org.mockito.plugins.InstantiatorProvider2 (Since 2.15.4)</a></h3>
1504  *
1505  * <p>{@link org.mockito.plugins.InstantiatorProvider} returned an internal API. Hence it was deprecated and replaced
1506  * by {@link org.mockito.plugins.InstantiatorProvider2}. Old {@link org.mockito.plugins.InstantiatorProvider
1507  * instantiator providers} will continue to work, but it is recommended to switch to the new API.</p>
1508  *
1509  * <h3 id="45">45. <a class="meaningful_link" href="#junit5_mockito" name="junit5_mockito">New JUnit Jupiter (JUnit5+) extension</a></h3>
1510  *
1511  * For integration with JUnit Jupiter (JUnit5+), use the `org.mockito:mockito-junit-jupiter` artifact.
1512  * For more information about the usage of the integration, see <a href="http://javadoc.io/page/org.mockito/mockito-junit-jupiter/latest/org/mockito/junit/jupiter/MockitoExtension.html">the JavaDoc of <code>MockitoExtension</code></a>.
1513  *
1514  * <h3 id="46">46. <a class="meaningful_link" href="#mockito_lenient" name="mockito_lenient">
1515  *       New <code>Mockito.lenient()</code> and <code>MockSettings.lenient()</code> methods (Since 2.20.0)</a></h3>
1516  *
1517  * Strict stubbing feature is available since early Mockito 2.
1518  * It is very useful because it drives cleaner tests and improved productivity.
1519  * Strict stubbing reports unnecessary stubs, detects stubbing argument mismatch and makes the tests more DRY ({@link Strictness#STRICT_STUBS}).
1520  * This comes with a trade-off: in some cases, you may get false negatives from strict stubbing.
1521  * To remedy those scenarios you can now configure specific stubbing to be lenient, while all the other stubbings and mocks use strict stubbing:
1522  *
1523  * <pre class="code"><code class="java">
1524  *   lenient().when(mock.foo()).thenReturn("ok");
1525  * </code></pre>
1526  *
1527  * If you want all the stubbings on a given mock to be lenient, you can configure the mock accordingly:
1528  *
1529  * <pre class="code"><code class="java">
1530  *   Foo mock = Mockito.mock(Foo.class, withSettings().lenient());
1531  * </code></pre>
1532  *
1533  * For more information refer to {@link Mockito#lenient()}.
1534  * Let us know how do you find the new feature by opening a GitHub issue to discuss!
1535  */
1536 @SuppressWarnings("unchecked")
1537 public class Mockito extends ArgumentMatchers {
1538 
1539     static final MockitoCore MOCKITO_CORE = new MockitoCore();
1540 
1541     /**
1542      * The default <code>Answer</code> of every mock <b>if</b> the mock was not stubbed.
1543      *
1544      * Typically it just returns some empty value.
1545      * <p>
1546      * {@link Answer} can be used to define the return values of unstubbed invocations.
1547      * <p>
1548      * This implementation first tries the global configuration and if there is no global configuration then
1549      * it will use a default answer that returns zeros, empty collections, nulls, etc.
1550      */
1551     public static final Answer<Object> RETURNS_DEFAULTS = Answers.RETURNS_DEFAULTS;
1552 
1553     /**
1554      * Optional <code>Answer</code> to be used with {@link Mockito#mock(Class, Answer)}.
1555      * <p>
1556      * {@link Answer} can be used to define the return values of unstubbed invocations.
1557      * <p>
1558      * This implementation can be helpful when working with legacy code.
1559      * Unstubbed methods often return null. If your code uses the object returned by an unstubbed call you get a NullPointerException.
1560      * This implementation of Answer <b>returns SmartNull instead of null</b>.
1561      * <code>SmartNull</code> gives nicer exception message than NPE because it points out the line where unstubbed method was called. You just click on the stack trace.
1562      * <p>
1563      * <code>ReturnsSmartNulls</code> first tries to return ordinary values (zeros, empty collections, empty string, etc.)
1564      * then it tries to return SmartNull. If the return type is final then plain <code>null</code> is returned.
1565      * <p>
1566      * <code>ReturnsSmartNulls</code> will be probably the default return values strategy in Mockito 3.0.0
1567      * <p>
1568      * Example:
1569      * <pre class="code"><code class="java">
1570      *   Foo mock = mock(Foo.class, RETURNS_SMART_NULLS);
1571      *
1572      *   //calling unstubbed method here:
1573      *   Stuff stuff = mock.getStuff();
1574      *
1575      *   //using object returned by unstubbed call:
1576      *   stuff.doSomething();
1577      *
1578      *   //Above doesn't yield NullPointerException this time!
1579      *   //Instead, SmartNullPointerException is thrown.
1580      *   //Exception's cause links to unstubbed <i>mock.getStuff()</i> - just click on the stack trace.
1581      * </code></pre>
1582      */
1583     public static final Answer<Object> RETURNS_SMART_NULLS = Answers.RETURNS_SMART_NULLS;
1584 
1585     /**
1586      * Optional <code>Answer</code> to be used with {@link Mockito#mock(Class, Answer)}
1587      * <p>
1588      * {@link Answer} can be used to define the return values of unstubbed invocations.
1589      * <p>
1590      * This implementation can be helpful when working with legacy code.
1591      * <p>
1592      * ReturnsMocks first tries to return ordinary values (zeros, empty collections, empty string, etc.)
1593      * then it tries to return mocks. If the return type cannot be mocked (e.g. is final) then plain <code>null</code> is returned.
1594      * <p>
1595      */
1596     public static final Answer<Object> RETURNS_MOCKS = Answers.RETURNS_MOCKS;
1597 
1598     /**
1599      * Optional <code>Answer</code> to be used with {@link Mockito#mock(Class, Answer)}.
1600      * <p>
1601      * Example that shows how deep stub works:
1602      * <pre class="code"><code class="java">
1603      *   Foo mock = mock(Foo.class, RETURNS_DEEP_STUBS);
1604      *
1605      *   // note that we're stubbing a chain of methods here: getBar().getName()
1606      *   when(mock.getBar().getName()).thenReturn("deep");
1607      *
1608      *   // note that we're chaining method calls: getBar().getName()
1609      *   assertEquals("deep", mock.getBar().getName());
1610      * </code></pre>
1611      * </p>
1612      *
1613      * <p>
1614      * <strong>WARNING: </strong>
1615      * This feature should rarely be required for regular clean code! Leave it for legacy code.
1616      * Mocking a mock to return a mock, to return a mock, (...), to return something meaningful
1617      * hints at violation of Law of Demeter or mocking a value object (a well known anti-pattern).
1618      * </p>
1619      *
1620      * <p>
1621      * Good quote I've seen one day on the web: <strong>every time a mock returns a mock a fairy dies</strong>.
1622      * </p>
1623      *
1624      * <p>
1625      * Please note that this answer will return existing mocks that matches the stub. This
1626      * behavior is ok with deep stubs and allows verification to work on the last mock of the chain.
1627      * <pre class="code"><code class="java">
1628      *   when(mock.getBar(anyString()).getThingy().getName()).thenReturn("deep");
1629      *
1630      *   mock.getBar("candy bar").getThingy().getName();
1631      *
1632      *   assertSame(mock.getBar(anyString()).getThingy().getName(), mock.getBar(anyString()).getThingy().getName());
1633      *   verify(mock.getBar("candy bar").getThingy()).getName();
1634      *   verify(mock.getBar(anyString()).getThingy()).getName();
1635      * </code></pre>
1636      * </p>
1637      *
1638      * <p>
1639      * Verification only works with the last mock in the chain. You can use verification modes.
1640      * <pre class="code"><code class="java">
1641      *   when(person.getAddress(anyString()).getStreet().getName()).thenReturn("deep");
1642      *   when(person.getAddress(anyString()).getStreet(Locale.ITALIAN).getName()).thenReturn("deep");
1643      *   when(person.getAddress(anyString()).getStreet(Locale.CHINESE).getName()).thenReturn("deep");
1644      *
1645      *   person.getAddress("the docks").getStreet().getName();
1646      *   person.getAddress("the docks").getStreet().getLongName();
1647      *   person.getAddress("the docks").getStreet(Locale.ITALIAN).getName();
1648      *   person.getAddress("the docks").getStreet(Locale.CHINESE).getName();
1649      *
1650      *   // note that we are actually referring to the very last mock in the stubbing chain.
1651      *   InOrder inOrder = inOrder(
1652      *       person.getAddress("the docks").getStreet(),
1653      *       person.getAddress("the docks").getStreet(Locale.CHINESE),
1654      *       person.getAddress("the docks").getStreet(Locale.ITALIAN)
1655      *   );
1656      *   inOrder.verify(person.getAddress("the docks").getStreet(), times(1)).getName();
1657      *   inOrder.verify(person.getAddress("the docks").getStreet()).getLongName();
1658      *   inOrder.verify(person.getAddress("the docks").getStreet(Locale.ITALIAN), atLeast(1)).getName();
1659      *   inOrder.verify(person.getAddress("the docks").getStreet(Locale.CHINESE)).getName();
1660      * </code></pre>
1661      * </p>
1662      *
1663      * <p>
1664      * How deep stub work internally?
1665      * <pre class="code"><code class="java">
1666      *   //this:
1667      *   Foo mock = mock(Foo.class, RETURNS_DEEP_STUBS);
1668      *   when(mock.getBar().getName(), "deep");
1669      *
1670      *   //is equivalent of
1671      *   Foo foo = mock(Foo.class);
1672      *   Bar bar = mock(Bar.class);
1673      *   when(foo.getBar()).thenReturn(bar);
1674      *   when(bar.getName()).thenReturn("deep");
1675      * </code></pre>
1676      * </p>
1677      *
1678      * <p>
1679      * This feature will not work when any return type of methods included in the chain cannot be mocked
1680      * (for example: is a primitive or a final class). This is because of java type system.
1681      * </p>
1682      */
1683     public static final Answer<Object> RETURNS_DEEP_STUBS = Answers.RETURNS_DEEP_STUBS;
1684 
1685     /**
1686      * Optional <code>Answer</code> to be used with {@link Mockito#mock(Class, Answer)}
1687      * <p>
1688      * {@link Answer} can be used to define the return values of unstubbed invocations.
1689      * <p>
1690      * This implementation can be helpful when working with legacy code.
1691      * When this implementation is used, unstubbed methods will delegate to the real implementation.
1692      * This is a way to create a partial mock object that calls real methods by default.
1693      * <p>
1694      * As usual you are going to read <b>the partial mock warning</b>:
1695      * Object oriented programming is more less tackling complexity by dividing the complexity into separate, specific, SRPy objects.
1696      * How does partial mock fit into this paradigm? Well, it just doesn't...
1697      * Partial mock usually means that the complexity has been moved to a different method on the same object.
1698      * In most cases, this is not the way you want to design your application.
1699      * <p>
1700      * However, there are rare cases when partial mocks come handy:
1701      * dealing with code you cannot change easily (3rd party interfaces, interim refactoring of legacy code etc.)
1702      * However, I wouldn't use partial mocks for new, test-driven & well-designed code.
1703      * <p>
1704      * Example:
1705      * <pre class="code"><code class="java">
1706      * Foo mock = mock(Foo.class, CALLS_REAL_METHODS);
1707      *
1708      * // this calls the real implementation of Foo.getSomething()
1709      * value = mock.getSomething();
1710      *
1711      * doReturn(fakeValue).when(mock).getSomething();
1712      *
1713      * // now fakeValue is returned
1714      * value = mock.getSomething();
1715      * </code></pre>
1716      *
1717      * <p>
1718      * <u>Note:</u> Stubbing partial mocks using <code>when(mock.getSomething()).thenReturn(fakeValue)</code>
1719      * syntax will call the real method. For partial mock it's recommended to use <code>doReturn</code> syntax.
1720      */
1721     public static final Answer<Object> CALLS_REAL_METHODS = Answers.CALLS_REAL_METHODS;
1722 
1723     /**
1724      * Optional <code>Answer</code> to be used with {@link Mockito#mock(Class, Answer)}.
1725      *
1726      * Allows Builder mocks to return itself whenever a method is invoked that returns a Type equal
1727      * to the class or a superclass.
1728      *
1729      * <p><b>Keep in mind this answer uses the return type of a method.
1730      * If this type is assignable to the class of the mock, it will return the mock.
1731      * Therefore if you have a method returning a superclass (for example {@code Object}) it will match and return the mock.</b></p>
1732      *
1733      * Consider a HttpBuilder used in a HttpRequesterWithHeaders.
1734      *
1735      * <pre class="code"><code class="java">
1736      * public class HttpRequesterWithHeaders {
1737      *
1738      *      private HttpBuilder builder;
1739      *
1740      *      public HttpRequesterWithHeaders(HttpBuilder builder) {
1741      *          this.builder = builder;
1742      *      }
1743      *
1744      *      public String request(String uri) {
1745      *          return builder.withUrl(uri)
1746      *                  .withHeader("Content-type: application/json")
1747      *                  .withHeader("Authorization: Bearer")
1748      *                  .request();
1749      *      }
1750      *  }
1751      *
1752      *  private static class HttpBuilder {
1753      *
1754      *      private String uri;
1755      *      private List&lt;String&gt; headers;
1756      *
1757      *      public HttpBuilder() {
1758      *          this.headers = new ArrayList&lt;String&gt;();
1759      *      }
1760      *
1761      *       public HttpBuilder withUrl(String uri) {
1762      *           this.uri = uri;
1763      *           return this;
1764      *       }
1765      *
1766      *       public HttpBuilder withHeader(String header) {
1767      *           this.headers.add(header);
1768      *           return this;
1769      *       }
1770      *
1771      *       public String request() {
1772      *          return uri + headers.toString();
1773      *       }
1774      *  }
1775      * </code></pre>
1776      *
1777      * The following test will succeed
1778      *
1779      * <pre><code>
1780      * &#064;Test
1781      *  public void use_full_builder_with_terminating_method() {
1782      *      HttpBuilder builder = mock(HttpBuilder.class, RETURNS_SELF);
1783      *      HttpRequesterWithHeaders requester = new HttpRequesterWithHeaders(builder);
1784      *      String response = "StatusCode: 200";
1785      *
1786      *      when(builder.request()).thenReturn(response);
1787      *
1788      *      assertThat(requester.request("URI")).isEqualTo(response);
1789      *  }
1790      * </code></pre>
1791      */
1792     public static final Answer<Object> RETURNS_SELF = Answers.RETURNS_SELF;
1793 
1794     /**
1795      * Creates mock object of given class or interface.
1796      * <p>
1797      * See examples in javadoc for {@link Mockito} class
1798      *
1799      * @param classToMock class or interface to mock
1800      * @return mock object
1801      */
1802     @CheckReturnValue
mock(Class<T> classToMock)1803     public static <T> T mock(Class<T> classToMock) {
1804         return mock(classToMock, withSettings());
1805     }
1806 
1807     /**
1808      * Specifies mock name. Naming mocks can be helpful for debugging - the name is used in all verification errors.
1809      * <p>
1810      * Beware that naming mocks is not a solution for complex code which uses too many mocks or collaborators.
1811      * <b>If you have too many mocks then refactor the code</b> so that it's easy to test/debug without necessity of naming mocks.
1812      * <p>
1813      * <b>If you use <code>&#064;Mock</code> annotation then you've got naming mocks for free!</b> <code>&#064;Mock</code> uses field name as mock name. {@link Mock Read more.}
1814      * <p>
1815      *
1816      * See examples in javadoc for {@link Mockito} class
1817      *
1818      * @param classToMock class or interface to mock
1819      * @param name of the mock
1820      * @return mock object
1821      */
1822     @CheckReturnValue
mock(Class<T> classToMock, String name)1823     public static <T> T mock(Class<T> classToMock, String name) {
1824         return mock(classToMock, withSettings()
1825                 .name(name)
1826                 .defaultAnswer(RETURNS_DEFAULTS));
1827     }
1828 
1829     /**
1830      * Returns a MockingDetails instance that enables inspecting a particular object for Mockito related information.
1831      * Can be used to find out if given object is a Mockito mock
1832      * or to find out if a given mock is a spy or mock.
1833      * <p>
1834      * In future Mockito versions MockingDetails may grow and provide other useful information about the mock,
1835      * e.g. invocations, stubbing info, etc.
1836      *
1837      * @param toInspect - object to inspect. null input is allowed.
1838      * @return A {@link org.mockito.MockingDetails} instance.
1839      * @since 1.9.5
1840      */
1841     @CheckReturnValue
mockingDetails(Object toInspect)1842     public static MockingDetails mockingDetails(Object toInspect) {
1843         return MOCKITO_CORE.mockingDetails(toInspect);
1844     }
1845 
1846     /**
1847      * Creates mock with a specified strategy for its answers to interactions.
1848      * It's quite an advanced feature and typically you don't need it to write decent tests.
1849      * However it can be helpful when working with legacy systems.
1850      * <p>
1851      * It is the default answer so it will be used <b>only when you don't</b> stub the method call.
1852      *
1853      * <pre class="code"><code class="java">
1854      *   Foo mock = mock(Foo.class, RETURNS_SMART_NULLS);
1855      *   Foo mockTwo = mock(Foo.class, new YourOwnAnswer());
1856      * </code></pre>
1857      *
1858      * <p>See examples in javadoc for {@link Mockito} class</p>
1859      *
1860      * @param classToMock class or interface to mock
1861      * @param defaultAnswer default answer for unstubbed methods
1862      *
1863      * @return mock object
1864      */
1865     @CheckReturnValue
mock(Class<T> classToMock, Answer defaultAnswer)1866     public static <T> T mock(Class<T> classToMock, Answer defaultAnswer) {
1867         return mock(classToMock, withSettings().defaultAnswer(defaultAnswer));
1868     }
1869 
1870     /**
1871      * Creates a mock with some non-standard settings.
1872      * <p>
1873      * The number of configuration points for a mock grows
1874      * so we need a fluent way to introduce new configuration without adding more and more overloaded Mockito.mock() methods.
1875      * Hence {@link MockSettings}.
1876      * <pre class="code"><code class="java">
1877      *   Listener mock = mock(Listener.class, withSettings()
1878      *     .name("firstListner").defaultBehavior(RETURNS_SMART_NULLS));
1879      *   );
1880      * </code></pre>
1881      * <b>Use it carefully and occasionally</b>. What might be reason your test needs non-standard mocks?
1882      * Is the code under test so complicated that it requires non-standard mocks?
1883      * Wouldn't you prefer to refactor the code under test so it is testable in a simple way?
1884      * <p>
1885      * See also {@link Mockito#withSettings()}
1886      * <p>
1887      * See examples in javadoc for {@link Mockito} class
1888      *
1889      * @param classToMock class or interface to mock
1890      * @param mockSettings additional mock settings
1891      * @return mock object
1892      */
1893     @CheckReturnValue
mock(Class<T> classToMock, MockSettings mockSettings)1894     public static <T> T mock(Class<T> classToMock, MockSettings mockSettings) {
1895         return MOCKITO_CORE.mock(classToMock, mockSettings);
1896     }
1897 
1898     /**
1899      * Creates a spy of the real object. The spy calls <b>real</b> methods unless they are stubbed.
1900      * <p>
1901      * Real spies should be used <b>carefully and occasionally</b>, for example when dealing with legacy code.
1902      * <p>
1903      * As usual you are going to read <b>the partial mock warning</b>:
1904      * Object oriented programming tackles complexity by dividing the complexity into separate, specific, SRPy objects.
1905      * How does partial mock fit into this paradigm? Well, it just doesn't...
1906      * Partial mock usually means that the complexity has been moved to a different method on the same object.
1907      * In most cases, this is not the way you want to design your application.
1908      * <p>
1909      * However, there are rare cases when partial mocks come handy:
1910      * dealing with code you cannot change easily (3rd party interfaces, interim refactoring of legacy code etc.)
1911      * However, I wouldn't use partial mocks for new, test-driven & well-designed code.
1912      * <p>
1913      * Example:
1914      *
1915      * <pre class="code"><code class="java">
1916      *   List list = new LinkedList();
1917      *   List spy = spy(list);
1918      *
1919      *   //optionally, you can stub out some methods:
1920      *   when(spy.size()).thenReturn(100);
1921      *
1922      *   //using the spy calls <b>real</b> methods
1923      *   spy.add("one");
1924      *   spy.add("two");
1925      *
1926      *   //prints "one" - the first element of a list
1927      *   System.out.println(spy.get(0));
1928      *
1929      *   //size() method was stubbed - 100 is printed
1930      *   System.out.println(spy.size());
1931      *
1932      *   //optionally, you can verify
1933      *   verify(spy).add("one");
1934      *   verify(spy).add("two");
1935      * </code></pre>
1936      *
1937      * <h4>Important gotcha on spying real objects!</h4>
1938      * <ol>
1939      * <li>Sometimes it's impossible or impractical to use {@link Mockito#when(Object)} for stubbing spies.
1940      * Therefore for spies it is recommended to always use <code>doReturn</code>|<code>Answer</code>|<code>Throw()</code>|<code>CallRealMethod</code>
1941      * family of methods for stubbing. Example:
1942      *
1943      * <pre class="code"><code class="java">
1944      *   List list = new LinkedList();
1945      *   List spy = spy(list);
1946      *
1947      *   //Impossible: real method is called so spy.get(0) throws IndexOutOfBoundsException (the list is yet empty)
1948      *   when(spy.get(0)).thenReturn("foo");
1949      *
1950      *   //You have to use doReturn() for stubbing
1951      *   doReturn("foo").when(spy).get(0);
1952      * </code></pre>
1953      * </li>
1954      *
1955      * <li>Mockito <b>*does not*</b> delegate calls to the passed real instance, instead it actually creates a copy of it.
1956      * So if you keep the real instance and interact with it, don't expect the spied to be aware of those interaction
1957      * and their effect on real instance state.
1958      * The corollary is that when an <b>*unstubbed*</b> method is called <b>*on the spy*</b> but <b>*not on the real instance*</b>,
1959      * you won't see any effects on the real instance.</li>
1960      *
1961      * <li>Watch out for final methods.
1962      * Mockito doesn't mock final methods so the bottom line is: when you spy on real objects + you try to stub a final method = trouble.
1963      * Also you won't be able to verify those method as well.
1964      * </li>
1965      * </ol>
1966      * <p>
1967      * See examples in javadoc for {@link Mockito} class
1968      *
1969      * <p>Note that the spy won't have any annotations of the spied type, because CGLIB won't rewrite them.
1970      * It may troublesome for code that rely on the spy to have these annotations.</p>
1971      *
1972      *
1973      * @param object
1974      *            to spy on
1975      * @return a spy of the real object
1976      */
1977     @CheckReturnValue
spy(T object)1978     public static <T> T spy(T object) {
1979         return MOCKITO_CORE.mock((Class<T>) object.getClass(), withSettings()
1980                 .spiedInstance(object)
1981                 .defaultAnswer(CALLS_REAL_METHODS));
1982     }
1983 
1984     /**
1985      * Please refer to the documentation of {@link #spy(Object)}.
1986      * Overusing spies hints at code design smells.
1987      * <p>
1988      * This method, in contrast to the original {@link #spy(Object)}, creates a spy based on class instead of an object.
1989      * Sometimes it is more convenient to create spy based on the class and avoid providing an instance of a spied object.
1990      * This is particularly useful for spying on abstract classes because they cannot be instantiated.
1991      * See also {@link MockSettings#useConstructor(Object...)}.
1992      * <p>
1993      * Examples:
1994      * <pre class="code"><code class="java">
1995      *   SomeAbstract spy = spy(SomeAbstract.class);
1996      *
1997      *   //Robust API, via settings builder:
1998      *   OtherAbstract spy = mock(OtherAbstract.class, withSettings()
1999      *      .useConstructor().defaultAnswer(CALLS_REAL_METHODS));
2000      *
2001      *   //Mocking a non-static inner abstract class:
2002      *   InnerAbstract spy = mock(InnerAbstract.class, withSettings()
2003      *      .useConstructor().outerInstance(outerInstance).defaultAnswer(CALLS_REAL_METHODS));
2004      * </code></pre>
2005      *
2006      * @param classToSpy the class to spy
2007      * @param <T> type of the spy
2008      * @return a spy of the provided class
2009      * @since 1.10.12
2010      */
2011     @Incubating
2012     @CheckReturnValue
spy(Class<T> classToSpy)2013     public static <T> T spy(Class<T> classToSpy) {
2014         return MOCKITO_CORE.mock(classToSpy, withSettings()
2015                 .useConstructor()
2016                 .defaultAnswer(CALLS_REAL_METHODS));
2017     }
2018 
2019     /**
2020      * Enables stubbing methods. Use it when you want the mock to return particular value when particular method is called.
2021      * <p>
2022      * Simply put: "<b>When</b> the x method is called <b>then</b> return y".
2023      *
2024      * <p>
2025      * Examples:
2026      *
2027      * <pre class="code"><code class="java">
2028      * <b>when</b>(mock.someMethod()).<b>thenReturn</b>(10);
2029      *
2030      * //you can use flexible argument matchers, e.g:
2031      * when(mock.someMethod(<b>anyString()</b>)).thenReturn(10);
2032      *
2033      * //setting exception to be thrown:
2034      * when(mock.someMethod("some arg")).thenThrow(new RuntimeException());
2035      *
2036      * //you can set different behavior for consecutive method calls.
2037      * //Last stubbing (e.g: thenReturn("foo")) determines the behavior of further consecutive calls.
2038      * when(mock.someMethod("some arg"))
2039      *  .thenThrow(new RuntimeException())
2040      *  .thenReturn("foo");
2041      *
2042      * //Alternative, shorter version for consecutive stubbing:
2043      * when(mock.someMethod("some arg"))
2044      *  .thenReturn("one", "two");
2045      * //is the same as:
2046      * when(mock.someMethod("some arg"))
2047      *  .thenReturn("one")
2048      *  .thenReturn("two");
2049      *
2050      * //shorter version for consecutive method calls throwing exceptions:
2051      * when(mock.someMethod("some arg"))
2052      *  .thenThrow(new RuntimeException(), new NullPointerException();
2053      *
2054      * </code></pre>
2055      *
2056      * For stubbing void methods with throwables see: {@link Mockito#doThrow(Throwable...)}
2057      * <p>
2058      * Stubbing can be overridden: for example common stubbing can go to fixture
2059      * setup but the test methods can override it.
2060      * Please note that overridding stubbing is a potential code smell that points out too much stubbing.
2061      * <p>
2062      * Once stubbed, the method will always return stubbed value regardless
2063      * of how many times it is called.
2064      * <p>
2065      * Last stubbing is more important - when you stubbed the same method with
2066      * the same arguments many times.
2067      * <p>
2068      * Although it is possible to verify a stubbed invocation, usually <b>it's just redundant</b>.
2069      * Let's say you've stubbed <code>foo.bar()</code>.
2070      * If your code cares what <code>foo.bar()</code> returns then something else breaks(often before even <code>verify()</code> gets executed).
2071      * If your code doesn't care what <code>get(0)</code> returns then it should not be stubbed.
2072      * Not convinced? See <a href="http://monkeyisland.pl/2008/04/26/asking-and-telling">here</a>.
2073      *
2074      * <p>
2075      * See examples in javadoc for {@link Mockito} class
2076      * @param methodCall method to be stubbed
2077      * @return OngoingStubbing object used to stub fluently.
2078      *         <strong>Do not</strong> create a reference to this returned object.
2079      */
2080     @CheckReturnValue
when(T methodCall)2081     public static <T> OngoingStubbing<T> when(T methodCall) {
2082         return MOCKITO_CORE.when(methodCall);
2083     }
2084 
2085     /**
2086      * Verifies certain behavior <b>happened once</b>.
2087      * <p>
2088      * Alias to <code>verify(mock, times(1))</code> E.g:
2089      * <pre class="code"><code class="java">
2090      *   verify(mock).someMethod("some arg");
2091      * </code></pre>
2092      * Above is equivalent to:
2093      * <pre class="code"><code class="java">
2094      *   verify(mock, times(1)).someMethod("some arg");
2095      * </code></pre>
2096      * <p>
2097      * Arguments passed are compared using <code>equals()</code> method.
2098      * Read about {@link ArgumentCaptor} or {@link ArgumentMatcher} to find out other ways of matching / asserting arguments passed.
2099      * <p>
2100      * Although it is possible to verify a stubbed invocation, usually <b>it's just redundant</b>.
2101      * Let's say you've stubbed <code>foo.bar()</code>.
2102      * If your code cares what <code>foo.bar()</code> returns then something else breaks(often before even <code>verify()</code> gets executed).
2103      * If your code doesn't care what <code>get(0)</code> returns then it should not be stubbed.
2104      * Not convinced? See <a href="http://monkeyisland.pl/2008/04/26/asking-and-telling">here</a>.
2105      *
2106      * <p>
2107      * See examples in javadoc for {@link Mockito} class
2108      *
2109      * @param mock to be verified
2110      * @return mock object itself
2111      */
2112     @CheckReturnValue
verify(T mock)2113     public static <T> T verify(T mock) {
2114         return MOCKITO_CORE.verify(mock, times(1));
2115     }
2116 
2117     /**
2118      * Verifies certain behavior happened at least once / exact number of times / never. E.g:
2119      * <pre class="code"><code class="java">
2120      *   verify(mock, times(5)).someMethod("was called five times");
2121      *
2122      *   verify(mock, atLeast(2)).someMethod("was called at least two times");
2123      *
2124      *   //you can use flexible argument matchers, e.g:
2125      *   verify(mock, atLeastOnce()).someMethod(<b>anyString()</b>);
2126      * </code></pre>
2127      *
2128      * <b>times(1) is the default</b> and can be omitted
2129      * <p>
2130      * Arguments passed are compared using <code>equals()</code> method.
2131      * Read about {@link ArgumentCaptor} or {@link ArgumentMatcher} to find out other ways of matching / asserting arguments passed.
2132      * <p>
2133      *
2134      * @param mock to be verified
2135      * @param mode times(x), atLeastOnce() or never()
2136      *
2137      * @return mock object itself
2138      */
2139     @CheckReturnValue
verify(T mock, VerificationMode mode)2140     public static <T> T verify(T mock, VerificationMode mode) {
2141         return MOCKITO_CORE.verify(mock, mode);
2142     }
2143 
2144     /**
2145      * Smart Mockito users hardly use this feature because they know it could be a sign of poor tests.
2146      * Normally, you don't need to reset your mocks, just create new mocks for each test method.
2147      * <p>
2148      * Instead of <code>#reset()</code> please consider writing simple, small and focused test methods over lengthy, over-specified tests.
2149      * <b>First potential code smell is <code>reset()</code> in the middle of the test method.</b> This probably means you're testing too much.
2150      * Follow the whisper of your test methods: "Please keep us small & focused on single behavior".
2151      * There are several threads about it on mockito mailing list.
2152      * <p>
2153      * The only reason we added <code>reset()</code> method is to
2154      * make it possible to work with container-injected mocks.
2155      * For more information see the FAQ (<a href="https://github.com/mockito/mockito/wiki/FAQ">here</a>).
2156      * <p>
2157      * <b>Don't harm yourself.</b> <code>reset()</code> in the middle of the test method is a code smell (you're probably testing too much).
2158      * <pre class="code"><code class="java">
2159      *   List mock = mock(List.class);
2160      *   when(mock.size()).thenReturn(10);
2161      *   mock.add(1);
2162      *
2163      *   reset(mock);
2164      *   //at this point the mock forgot any interactions & stubbing
2165      * </code></pre>
2166      *
2167      * @param <T> The Type of the mocks
2168      * @param mocks to be reset
2169      */
reset(T .... mocks)2170     public static <T> void reset(T ... mocks) {
2171         MOCKITO_CORE.reset(mocks);
2172     }
2173 
2174     /**
2175      * Use this method in order to only clear invocations, when stubbing is non-trivial. Use-cases can be:
2176      * <ul>
2177      *     <li>You are using a dependency injection framework to inject your mocks.</li>
2178      *     <li>The mock is used in a stateful scenario. For example a class is Singleton which depends on your mock.</li>
2179      * </ul>
2180      *
2181      * <b>Try to avoid this method at all costs. Only clear invocations if you are unable to efficiently test your program.</b>
2182      * @param <T> The type of the mocks
2183      * @param mocks The mocks to clear the invocations for
2184      */
clearInvocations(T .... mocks)2185     public static <T> void clearInvocations(T ... mocks) {
2186         MOCKITO_CORE.clearInvocations(mocks);
2187     }
2188 
2189     /**
2190      * Checks if any of given mocks has any unverified interaction.
2191      * <p>
2192      * You can use this method after you verified your mocks - to make sure that nothing
2193      * else was invoked on your mocks.
2194      * <p>
2195      * See also {@link Mockito#never()} - it is more explicit and communicates the intent well.
2196      * <p>
2197      * Stubbed invocations (if called) are also treated as interactions.
2198      * If you want stubbed invocations automatically verified, check out {@link Strictness#STRICT_STUBS} feature
2199      * introduced in Mockito 2.3.0.
2200      * If you want to ignore stubs for verification, see {@link #ignoreStubs(Object...)}.
2201      * <p>
2202      * A word of <b>warning</b>:
2203      * Some users who did a lot of classic, expect-run-verify mocking tend to use <code>verifyNoMoreInteractions()</code> very often, even in every test method.
2204      * <code>verifyNoMoreInteractions()</code> is not recommended to use in every test method.
2205      * <code>verifyNoMoreInteractions()</code> is a handy assertion from the interaction testing toolkit. Use it only when it's relevant.
2206      * Abusing it leads to overspecified, less maintainable tests. You can find further reading
2207      * <a href="http://monkeyisland.pl/2008/07/12/should-i-worry-about-the-unexpected/">here</a>.
2208      * <p>
2209      * This method will also detect unverified invocations that occurred before the test method,
2210      * for example: in <code>setUp()</code>, <code>&#064;Before</code> method or in constructor.
2211      * Consider writing nice code that makes interactions only in test methods.
2212      *
2213      * <p>
2214      * Example:
2215      *
2216      * <pre class="code"><code class="java">
2217      * //interactions
2218      * mock.doSomething();
2219      * mock.doSomethingUnexpected();
2220      *
2221      * //verification
2222      * verify(mock).doSomething();
2223      *
2224      * //following will fail because 'doSomethingUnexpected()' is unexpected
2225      * verifyNoMoreInteractions(mock);
2226      *
2227      * </code></pre>
2228      *
2229      * See examples in javadoc for {@link Mockito} class
2230      *
2231      * @param mocks to be verified
2232      */
verifyNoMoreInteractions(Object... mocks)2233     public static void verifyNoMoreInteractions(Object... mocks) {
2234         MOCKITO_CORE.verifyNoMoreInteractions(mocks);
2235     }
2236 
2237     /**
2238      * Verifies that no interactions happened on given mocks beyond the previously verified interactions.<br/>
2239      * This method has the same behavior as {@link #verifyNoMoreInteractions(Object...)}.
2240      *
2241      * @param mocks to be verified
2242      */
verifyZeroInteractions(Object... mocks)2243     public static void verifyZeroInteractions(Object... mocks) {
2244         MOCKITO_CORE.verifyNoMoreInteractions(mocks);
2245     }
2246 
2247     /**
2248      * Use <code>doThrow()</code> when you want to stub the void method with an exception.
2249      * <p>
2250      * Stubbing voids requires different approach from {@link Mockito#when(Object)} because the compiler
2251      * does not like void methods inside brackets...
2252      * <p>
2253      * Example:
2254      *
2255      * <pre class="code"><code class="java">
2256      *   doThrow(new RuntimeException()).when(mock).someVoidMethod();
2257      * </code></pre>
2258      *
2259      * @param toBeThrown to be thrown when the stubbed method is called
2260      * @return stubber - to select a method for stubbing
2261      */
2262     @CheckReturnValue
doThrow(Throwable... toBeThrown)2263     public static Stubber doThrow(Throwable... toBeThrown) {
2264         return MOCKITO_CORE.stubber().doThrow(toBeThrown);
2265     }
2266 
2267     /**
2268      * Use <code>doThrow()</code> when you want to stub the void method with an exception.
2269      * <p>
2270      * A new exception instance will be created for each method invocation.
2271      * <p>
2272      * Stubbing voids requires different approach from {@link Mockito#when(Object)} because the compiler
2273      * does not like void methods inside brackets...
2274      * <p>
2275      * Example:
2276      *
2277      * <pre class="code"><code class="java">
2278      *   doThrow(RuntimeException.class).when(mock).someVoidMethod();
2279      * </code></pre>
2280      *
2281      * @param toBeThrown to be thrown when the stubbed method is called
2282      * @return stubber - to select a method for stubbing
2283      * @since 2.1.0
2284      */
2285     @CheckReturnValue
doThrow(Class<? extends Throwable> toBeThrown)2286     public static Stubber doThrow(Class<? extends Throwable> toBeThrown) {
2287         return MOCKITO_CORE.stubber().doThrow(toBeThrown);
2288     }
2289 
2290     /**
2291      * Same as {@link #doThrow(Class)} but sets consecutive exception classes to be thrown. Remember to use
2292      * <code>doThrow()</code> when you want to stub the void method to throw several exception of specified class.
2293      * <p>
2294      * A new exception instance will be created for each method invocation.
2295      * <p>
2296      * Stubbing voids requires different approach from {@link Mockito#when(Object)} because the compiler
2297      * does not like void methods inside brackets...
2298      * <p>
2299      * Example:
2300      *
2301      * <pre class="code"><code class="java">
2302      *   doThrow(RuntimeException.class, BigFailure.class).when(mock).someVoidMethod();
2303      * </code></pre>
2304      *
2305      * @param toBeThrown to be thrown when the stubbed method is called
2306      * @param toBeThrownNext next to be thrown when the stubbed method is called
2307      * @return stubber - to select a method for stubbing
2308      * @since 2.1.0
2309      */
2310     // Additional method helps users of JDK7+ to hide heap pollution / unchecked generics array creation
2311     @SuppressWarnings ({"unchecked", "varargs"})
2312     @CheckReturnValue
doThrow(Class<? extends Throwable> toBeThrown, Class<? extends Throwable>... toBeThrownNext)2313     public static Stubber doThrow(Class<? extends Throwable> toBeThrown, Class<? extends Throwable>... toBeThrownNext) {
2314         return MOCKITO_CORE.stubber().doThrow(toBeThrown, toBeThrownNext);
2315     }
2316 
2317 
2318     /**
2319      * Use <code>doCallRealMethod()</code> when you want to call the real implementation of a method.
2320      * <p>
2321      * As usual you are going to read <b>the partial mock warning</b>:
2322      * Object oriented programming is more less tackling complexity by dividing the complexity into separate, specific, SRPy objects.
2323      * How does partial mock fit into this paradigm? Well, it just doesn't...
2324      * Partial mock usually means that the complexity has been moved to a different method on the same object.
2325      * In most cases, this is not the way you want to design your application.
2326      * <p>
2327      * However, there are rare cases when partial mocks come handy:
2328      * dealing with code you cannot change easily (3rd party interfaces, interim refactoring of legacy code etc.)
2329      * However, I wouldn't use partial mocks for new, test-driven & well-designed code.
2330      * <p>
2331      * See also javadoc {@link Mockito#spy(Object)} to find out more about partial mocks.
2332      * <b>Mockito.spy() is a recommended way of creating partial mocks.</b>
2333      * The reason is it guarantees real methods are called against correctly constructed object because you're responsible for constructing the object passed to spy() method.
2334      * <p>
2335      * Example:
2336      * <pre class="code"><code class="java">
2337      *   Foo mock = mock(Foo.class);
2338      *   doCallRealMethod().when(mock).someVoidMethod();
2339      *
2340      *   // this will call the real implementation of Foo.someVoidMethod()
2341      *   mock.someVoidMethod();
2342      * </code></pre>
2343      * <p>
2344      * See examples in javadoc for {@link Mockito} class
2345      *
2346      * @return stubber - to select a method for stubbing
2347      * @since 1.9.5
2348      */
2349     @CheckReturnValue
doCallRealMethod()2350     public static Stubber doCallRealMethod() {
2351         return MOCKITO_CORE.stubber().doCallRealMethod();
2352     }
2353 
2354     /**
2355      * Use <code>doAnswer()</code> when you want to stub a void method with generic {@link Answer}.
2356      * <p>
2357      * Stubbing voids requires different approach from {@link Mockito#when(Object)} because the compiler does not like void methods inside brackets...
2358      * <p>
2359      * Example:
2360      *
2361      * <pre class="code"><code class="java">
2362      *  doAnswer(new Answer() {
2363      *      public Object answer(InvocationOnMock invocation) {
2364      *          Object[] args = invocation.getArguments();
2365      *          Mock mock = invocation.getMock();
2366      *          return null;
2367      *      }})
2368      *  .when(mock).someMethod();
2369      * </code></pre>
2370      * <p>
2371      * See examples in javadoc for {@link Mockito} class
2372      *
2373      * @param answer to answer when the stubbed method is called
2374      * @return stubber - to select a method for stubbing
2375      */
2376     @CheckReturnValue
doAnswer(Answer answer)2377     public static Stubber doAnswer(Answer answer) {
2378         return MOCKITO_CORE.stubber().doAnswer(answer);
2379     }
2380 
2381     /**
2382      * Use <code>doNothing()</code> for setting void methods to do nothing. <b>Beware that void methods on mocks do nothing by default!</b>
2383      * However, there are rare situations when doNothing() comes handy:
2384      * <p>
2385      * <ol>
2386      * <li>Stubbing consecutive calls on a void method:
2387      * <pre class="code"><code class="java">
2388      *   doNothing().
2389      *   doThrow(new RuntimeException())
2390      *   .when(mock).someVoidMethod();
2391      *
2392      *   //does nothing the first time:
2393      *   mock.someVoidMethod();
2394      *
2395      *   //throws RuntimeException the next time:
2396      *   mock.someVoidMethod();
2397      * </code></pre>
2398      * </li>
2399      * <li>When you spy real objects and you want the void method to do nothing:
2400      * <pre class="code"><code class="java">
2401      *   List list = new LinkedList();
2402      *   List spy = spy(list);
2403      *
2404      *   //let's make clear() do nothing
2405      *   doNothing().when(spy).clear();
2406      *
2407      *   spy.add("one");
2408      *
2409      *   //clear() does nothing, so the list still contains "one"
2410      *   spy.clear();
2411      * </code></pre>
2412      * </li>
2413      * </ol>
2414      * <p>
2415      * See examples in javadoc for {@link Mockito} class
2416      *
2417      * @return stubber - to select a method for stubbing
2418      */
2419     @CheckReturnValue
doNothing()2420     public static Stubber doNothing() {
2421         return MOCKITO_CORE.stubber().doNothing();
2422     }
2423 
2424     /**
2425      * Use <code>doReturn()</code> in those rare occasions when you cannot use {@link Mockito#when(Object)}.
2426      * <p>
2427      * <b>Beware that {@link Mockito#when(Object)} is always recommended for stubbing because it is argument type-safe
2428      * and more readable</b> (especially when stubbing consecutive calls).
2429      * <p>
2430      * Here are those rare occasions when doReturn() comes handy:
2431      * <p>
2432      *
2433      * <ol>
2434      * <li>When spying real objects and calling real methods on a spy brings side effects
2435      *
2436      * <pre class="code"><code class="java">
2437      *   List list = new LinkedList();
2438      *   List spy = spy(list);
2439      *
2440      *   //Impossible: real method is called so spy.get(0) throws IndexOutOfBoundsException (the list is yet empty)
2441      *   when(spy.get(0)).thenReturn("foo");
2442      *
2443      *   //You have to use doReturn() for stubbing:
2444      *   doReturn("foo").when(spy).get(0);
2445      * </code></pre>
2446      * </li>
2447      *
2448      * <li>Overriding a previous exception-stubbing:
2449      * <pre class="code"><code class="java">
2450      *   when(mock.foo()).thenThrow(new RuntimeException());
2451      *
2452      *   //Impossible: the exception-stubbed foo() method is called so RuntimeException is thrown.
2453      *   when(mock.foo()).thenReturn("bar");
2454      *
2455      *   //You have to use doReturn() for stubbing:
2456      *   doReturn("bar").when(mock).foo();
2457      * </code></pre>
2458      * </li>
2459      * </ol>
2460      *
2461      * Above scenarios shows a tradeoff of Mockito's elegant syntax. Note that the scenarios are very rare, though.
2462      * Spying should be sporadic and overriding exception-stubbing is very rare. Not to mention that in general
2463      * overridding stubbing is a potential code smell that points out too much stubbing.
2464      * <p>
2465      * See examples in javadoc for {@link Mockito} class
2466      *
2467      * @param toBeReturned to be returned when the stubbed method is called
2468      * @return stubber - to select a method for stubbing
2469      */
2470     @CheckReturnValue
doReturn(Object toBeReturned)2471     public static Stubber doReturn(Object toBeReturned) {
2472         return MOCKITO_CORE.stubber().doReturn(toBeReturned);
2473     }
2474 
2475     /**
2476      * Same as {@link #doReturn(Object)} but sets consecutive values to be returned. Remember to use
2477      * <code>doReturn()</code> in those rare occasions when you cannot use {@link Mockito#when(Object)}.
2478      * <p>
2479      * <b>Beware that {@link Mockito#when(Object)} is always recommended for stubbing because it is argument type-safe
2480      * and more readable</b> (especially when stubbing consecutive calls).
2481      * <p>
2482      * Here are those rare occasions when doReturn() comes handy:
2483      * <p>
2484      *
2485      * <ol>
2486      * <li>When spying real objects and calling real methods on a spy brings side effects
2487      *
2488      * <pre class="code"><code class="java">
2489      *   List list = new LinkedList();
2490      *   List spy = spy(list);
2491      *
2492      *   //Impossible: real method is called so spy.get(0) throws IndexOutOfBoundsException (the list is yet empty)
2493      *   when(spy.get(0)).thenReturn("foo", "bar", "qix");
2494      *
2495      *   //You have to use doReturn() for stubbing:
2496      *   doReturn("foo", "bar", "qix").when(spy).get(0);
2497      * </code></pre>
2498      * </li>
2499      *
2500      * <li>Overriding a previous exception-stubbing:
2501      * <pre class="code"><code class="java">
2502      *   when(mock.foo()).thenThrow(new RuntimeException());
2503      *
2504      *   //Impossible: the exception-stubbed foo() method is called so RuntimeException is thrown.
2505      *   when(mock.foo()).thenReturn("bar", "foo", "qix");
2506      *
2507      *   //You have to use doReturn() for stubbing:
2508      *   doReturn("bar", "foo", "qix").when(mock).foo();
2509      * </code></pre>
2510      * </li>
2511      * </ol>
2512      *
2513      * Above scenarios shows a trade-off of Mockito's elegant syntax. Note that the scenarios are very rare, though.
2514      * Spying should be sporadic and overriding exception-stubbing is very rare. Not to mention that in general
2515      * overridding stubbing is a potential code smell that points out too much stubbing.
2516      * <p>
2517      * See examples in javadoc for {@link Mockito} class
2518      *
2519      * @param toBeReturned to be returned when the stubbed method is called
2520      * @param toBeReturnedNext to be returned in consecutive calls when the stubbed method is called
2521      * @return stubber - to select a method for stubbing
2522      * @since 2.1.0
2523      */
2524     @SuppressWarnings({"unchecked", "varargs"})
2525     @CheckReturnValue
doReturn(Object toBeReturned, Object... toBeReturnedNext)2526     public static Stubber doReturn(Object toBeReturned, Object... toBeReturnedNext) {
2527         return MOCKITO_CORE.stubber().doReturn(toBeReturned, toBeReturnedNext);
2528     }
2529 
2530     /**
2531      * Creates {@link org.mockito.InOrder} object that allows verifying mocks in order.
2532      *
2533      * <pre class="code"><code class="java">
2534      *   InOrder inOrder = inOrder(firstMock, secondMock);
2535      *
2536      *   inOrder.verify(firstMock).add("was called first");
2537      *   inOrder.verify(secondMock).add("was called second");
2538      * </code></pre>
2539      *
2540      * Verification in order is flexible - <b>you don't have to verify all interactions</b> one-by-one
2541      * but only those that you are interested in testing in order.
2542      * <p>
2543      * Also, you can create InOrder object passing only mocks that are relevant for in-order verification.
2544      * <p>
2545      * <code>InOrder</code> verification is 'greedy', but you will hardly ever notice it.
2546      * If you want to find out more, read
2547      * <a href="https://github.com/mockito/mockito/wiki/Greedy-algorithm-of-verfication-InOrder">this wiki page</a>.
2548      * <p>
2549      * As of Mockito 1.8.4 you can verifyNoMoreInvocations() in order-sensitive way. Read more: {@link InOrder#verifyNoMoreInteractions()}
2550      * <p>
2551      * See examples in javadoc for {@link Mockito} class
2552      *
2553      * @param mocks to be verified in order
2554      *
2555      * @return InOrder object to be used to verify in order
2556      */
2557     @CheckReturnValue
inOrder(Object... mocks)2558     public static InOrder inOrder(Object... mocks) {
2559         return MOCKITO_CORE.inOrder(mocks);
2560     }
2561 
2562     /**
2563      * Ignores stubbed methods of given mocks for the sake of verification.
2564      * Please consider using {@link Strictness#STRICT_STUBS} feature which eliminates the need for <code>ignoreStubs()</code>
2565      * and provides other benefits.
2566      * <p>
2567      * <code>ignoreStubs()</code> is sometimes useful when coupled with <code>verifyNoMoreInteractions()</code> or verification <code>inOrder()</code>.
2568      * Helps avoiding redundant verification of stubbed calls - typically we're not interested in verifying stubs.
2569      * <p>
2570      * <b>Warning</b>, <code>ignoreStubs()</code> might lead to overuse of <code>verifyNoMoreInteractions(ignoreStubs(...));</code>
2571      * Bear in mind that Mockito does not recommend bombarding every test with <code>verifyNoMoreInteractions()</code>
2572      * for the reasons outlined in javadoc for {@link Mockito#verifyNoMoreInteractions(Object...)}
2573      * Other words: all <b>*stubbed*</b> methods of given mocks are marked <b>*verified*</b> so that they don't get in a way during verifyNoMoreInteractions().
2574      * <p>
2575      * This method <b>changes the input mocks</b>! This method returns input mocks just for convenience.
2576      * <p>
2577      * Ignored stubs will also be ignored for verification inOrder, including {@link org.mockito.InOrder#verifyNoMoreInteractions()}.
2578      * See the second example.
2579      * <p>
2580      * Example:
2581      * <pre class="code"><code class="java">
2582      *  //mocking lists for the sake of the example (if you mock List in real you will burn in hell)
2583      *  List mock1 = mock(List.class), mock2 = mock(List.class);
2584      *
2585      *  //stubbing mocks:
2586      *  when(mock1.get(0)).thenReturn(10);
2587      *  when(mock2.get(0)).thenReturn(20);
2588      *
2589      *  //using mocks by calling stubbed get(0) methods:
2590      *  System.out.println(mock1.get(0)); //prints 10
2591      *  System.out.println(mock2.get(0)); //prints 20
2592      *
2593      *  //using mocks by calling clear() methods:
2594      *  mock1.clear();
2595      *  mock2.clear();
2596      *
2597      *  //verification:
2598      *  verify(mock1).clear();
2599      *  verify(mock2).clear();
2600      *
2601      *  //verifyNoMoreInteractions() fails because get() methods were not accounted for.
2602      *  try { verifyNoMoreInteractions(mock1, mock2); } catch (NoInteractionsWanted e);
2603      *
2604      *  //However, if we ignore stubbed methods then we can verifyNoMoreInteractions()
2605      *  verifyNoMoreInteractions(ignoreStubs(mock1, mock2));
2606      *
2607      *  //Remember that ignoreStubs() <b>*changes*</b> the input mocks and returns them for convenience.
2608      * </code></pre>
2609      * Ignoring stubs can be used with <b>verification in order</b>:
2610      * <pre class="code"><code class="java">
2611      *  List list = mock(List.class);
2612      *  when(list.get(0)).thenReturn("foo");
2613      *
2614      *  list.add(0);
2615      *  list.clear();
2616      *  System.out.println(list.get(0)); //we don't want to verify this
2617      *
2618      *  InOrder inOrder = inOrder(ignoreStubs(list));
2619      *  inOrder.verify(list).add(0);
2620      *  inOrder.verify(list).clear();
2621      *  inOrder.verifyNoMoreInteractions();
2622      * </code></pre>
2623      * Stubbed invocations are automatically verified with {@link Strictness#STRICT_STUBS} feature
2624      * and it eliminates the need for <code>ignoreStubs()</code>. Example below uses JUnit Rules:
2625      * <pre class="code"><code class="java">
2626      *  &#064;Rule public MockitoRule mockito = MockitoJUnit.rule().strictness(Strictness.STRICT_STUBS);
2627      *
2628      *  List list = mock(List.class);
2629      *  when(list.get(0)).thenReturn("foo");
2630      *
2631      *  list.size();
2632      *  verify(list).size();
2633      *
2634      *  list.get(0); // Automatically verified by STRICT_STUBS
2635      *  verifyNoMoreInteractions(list); // No need of ignoreStubs()
2636      * </code></pre>
2637      *
2638      * @since 1.9.0
2639      * @param mocks input mocks that will be changed
2640      * @return the same mocks that were passed in as parameters
2641      */
ignoreStubs(Object... mocks)2642     public static Object[] ignoreStubs(Object... mocks) {
2643         return MOCKITO_CORE.ignoreStubs(mocks);
2644     }
2645 
2646     /**
2647      * Allows verifying exact number of invocations. E.g:
2648      * <pre class="code"><code class="java">
2649      *   verify(mock, times(2)).someMethod("some arg");
2650      * </code></pre>
2651      *
2652      * See examples in javadoc for {@link Mockito} class
2653      *
2654      * @param wantedNumberOfInvocations wanted number of invocations
2655      *
2656      * @return verification mode
2657      */
2658     @CheckReturnValue
times(int wantedNumberOfInvocations)2659     public static VerificationMode times(int wantedNumberOfInvocations) {
2660         return VerificationModeFactory.times(wantedNumberOfInvocations);
2661     }
2662 
2663     /**
2664      * Alias to <code>times(0)</code>, see {@link Mockito#times(int)}
2665      * <p>
2666      * Verifies that interaction did not happen. E.g:
2667      * <pre class="code"><code class="java">
2668      *   verify(mock, never()).someMethod();
2669      * </code></pre>
2670      *
2671      * <p>
2672      * If you want to verify there were NO interactions with the mock
2673      * check out {@link Mockito#verifyZeroInteractions(Object...)}
2674      * or {@link Mockito#verifyNoMoreInteractions(Object...)}
2675      * <p>
2676      * See examples in javadoc for {@link Mockito} class
2677      *
2678      * @return verification mode
2679      */
2680     @CheckReturnValue
never()2681     public static VerificationMode never() {
2682         return times(0);
2683     }
2684 
2685     /**
2686      * Allows at-least-once verification. E.g:
2687      * <pre class="code"><code class="java">
2688      *   verify(mock, atLeastOnce()).someMethod("some arg");
2689      * </code></pre>
2690      * Alias to <code>atLeast(1)</code>.
2691      * <p>
2692      * See examples in javadoc for {@link Mockito} class
2693      *
2694      * @return verification mode
2695      */
2696     @CheckReturnValue
atLeastOnce()2697     public static VerificationMode atLeastOnce() {
2698         return VerificationModeFactory.atLeastOnce();
2699     }
2700 
2701     /**
2702      * Allows at-least-x verification. E.g:
2703      * <pre class="code"><code class="java">
2704      *   verify(mock, atLeast(3)).someMethod("some arg");
2705      * </code></pre>
2706      *
2707      * See examples in javadoc for {@link Mockito} class
2708      *
2709      * @param minNumberOfInvocations minimum number of invocations
2710      *
2711      * @return verification mode
2712      */
2713     @CheckReturnValue
atLeast(int minNumberOfInvocations)2714     public static VerificationMode atLeast(int minNumberOfInvocations) {
2715         return VerificationModeFactory.atLeast(minNumberOfInvocations);
2716     }
2717 
2718     /**
2719      * Allows at-most-x verification. E.g:
2720      * <pre class="code"><code class="java">
2721      *   verify(mock, atMost(3)).someMethod("some arg");
2722      * </code></pre>
2723      *
2724      * See examples in javadoc for {@link Mockito} class
2725      *
2726      * @param maxNumberOfInvocations max number of invocations
2727      *
2728      * @return verification mode
2729      */
2730     @CheckReturnValue
atMost(int maxNumberOfInvocations)2731     public static VerificationMode atMost(int maxNumberOfInvocations) {
2732         return VerificationModeFactory.atMost(maxNumberOfInvocations);
2733     }
2734 
2735     /**
2736      * Allows non-greedy verification in order.  For example
2737      * <pre class="code"><code class="java">
2738      *   inOrder.verify( mock, calls( 2 )).someMethod( "some arg" );
2739      * </code></pre>
2740      * <ul>
2741      * <li>will not fail if the method is called 3 times, unlike times( 2 )</li>
2742      * <li>will not mark the third invocation as verified, unlike atLeast( 2 )</li>
2743      * </ul>
2744      * This verification mode can only be used with in order verification.
2745      * @param wantedNumberOfInvocations number of invocations to verify
2746      * @return  verification mode
2747      */
2748     @CheckReturnValue
calls( int wantedNumberOfInvocations )2749     public static VerificationMode calls( int wantedNumberOfInvocations ){
2750         return VerificationModeFactory.calls( wantedNumberOfInvocations );
2751     }
2752 
2753     /**
2754      * Allows checking if given method was the only one invoked. E.g:
2755      * <pre class="code"><code class="java">
2756      *   verify(mock, only()).someMethod();
2757      *   //above is a shorthand for following 2 lines of code:
2758      *   verify(mock).someMethod();
2759      *   verifyNoMoreInvocations(mock);
2760      * </code></pre>
2761      *
2762      * <p>
2763      * See also {@link Mockito#verifyNoMoreInteractions(Object...)}
2764      * <p>
2765      * See examples in javadoc for {@link Mockito} class
2766      *
2767      * @return verification mode
2768      */
2769     @CheckReturnValue
only()2770     public static VerificationMode only() {
2771         return VerificationModeFactory.only();
2772     }
2773 
2774     /**
2775      * Verification will be triggered after given amount of millis, allowing testing of async code.
2776      * Useful when interactions with the mock object did not happened yet.
2777      * Extensive use of after() method can be a code smell - there are better ways of testing concurrent code.
2778      * <p>
2779      * See also {@link #after(long)} method for testing async code.
2780      * Differences between {@code timeout()} and {@code after} are explained in Javadoc for {@link #after(long)}.
2781      * <p>
2782      * Extensive use of {@code timeout()} method can be a code smell - there are better ways of testing concurrent code.
2783      * <pre class="code"><code class="java">
2784      *   //passes when someMethod() is called no later than within 100 ms
2785      *   //exits immediately when verification is satisfied (e.g. may not wait full 100 ms)
2786      *   verify(mock, timeout(100)).someMethod();
2787      *   //above is an alias to:
2788      *   verify(mock, timeout(100).times(1)).someMethod();
2789      *
2790      *   //passes as soon as someMethod() has been called 2 times under 100 ms
2791      *   verify(mock, timeout(100).times(2)).someMethod();
2792      *
2793      *   //equivalent: this also passes as soon as someMethod() has been called 2 times under 100 ms
2794      *   verify(mock, timeout(100).atLeast(2)).someMethod();
2795      * </code></pre>
2796      *
2797      * See examples in javadoc for {@link Mockito} class
2798      *
2799      * @param millis - duration in milliseconds
2800      *
2801      * @return object that allows fluent specification of the verification (times(x), atLeast(y), etc.)
2802      */
2803     @CheckReturnValue
timeout(long millis)2804     public static VerificationWithTimeout timeout(long millis) {
2805         return new Timeout(millis, VerificationModeFactory.times(1));
2806     }
2807 
2808     /**
2809      * Verification will be triggered after given amount of millis, allowing testing of async code.
2810      * Useful when interactions with the mock object did not happened yet.
2811      * Extensive use of after() method can be a code smell - there are better ways of testing concurrent code.
2812      * <p>
2813      * Not yet implemented to work with InOrder verification.
2814      * <p>
2815      * See also {@link #timeout(long)} method for testing async code.
2816      * Differences between {@code timeout()} and {@code after()} are explained below.
2817      *
2818      * <pre class="code"><code class="java">
2819      *   //passes after 100ms, if someMethod() has only been called once at that time.
2820      *   verify(mock, after(100)).someMethod();
2821      *   //above is an alias to:
2822      *   verify(mock, after(100).times(1)).someMethod();
2823      *
2824      *   //passes if someMethod() is called <b>*exactly*</b> 2 times, as tested after 100 millis
2825      *   verify(mock, after(100).times(2)).someMethod();
2826      *
2827      *   //passes if someMethod() has not been called, as tested after 100 millis
2828      *   verify(mock, after(100).never()).someMethod();
2829      *
2830      *   //verifies someMethod() after a given time span using given verification mode
2831      *   //useful only if you have your own custom verification modes.
2832      *   verify(mock, new After(100, yourOwnVerificationMode)).someMethod();
2833      * </code></pre>
2834      *
2835      * <strong>timeout() vs. after()</strong>
2836      * <ul>
2837      *     <li>timeout() exits immediately with success when verification passes</li>
2838      *     <li>after() awaits full duration to check if verification passes</li>
2839      * </ul>
2840      * Examples:
2841      * <pre class="code"><code class="java">
2842      *   //1.
2843      *   mock.foo();
2844      *   verify(mock, after(1000)).foo();
2845      *   //waits 1000 millis and succeeds
2846      *
2847      *   //2.
2848      *   mock.foo();
2849      *   verify(mock, timeout(1000)).foo();
2850      *   //succeeds immediately
2851      * </code></pre>
2852      *
2853      * See examples in javadoc for {@link Mockito} class
2854      *
2855      * @param millis - duration in milliseconds
2856      *
2857      * @return object that allows fluent specification of the verification
2858      */
2859     @CheckReturnValue
after(long millis)2860     public static VerificationAfterDelay after(long millis) {
2861         return new After(millis, VerificationModeFactory.times(1));
2862     }
2863 
2864     /**
2865      * First of all, in case of any trouble, I encourage you to read the Mockito FAQ: <a href="https://github.com/mockito/mockito/wiki/FAQ">https://github.com/mockito/mockito/wiki/FAQ</a>
2866      * <p>
2867      * In case of questions you may also post to mockito mailing list: <a href="http://groups.google.com/group/mockito">http://groups.google.com/group/mockito</a>
2868      * <p>
2869      * <code>validateMockitoUsage()</code> <b>explicitly validates</b> the framework state to detect invalid use of Mockito.
2870      * However, this feature is optional <b>because Mockito validates the usage all the time...</b> but there is a gotcha so read on.
2871      * <p>
2872      * Examples of incorrect use:
2873      * <pre class="code"><code class="java">
2874      * //Oops, thenReturn() part is missing:
2875      * when(mock.get());
2876      *
2877      * //Oops, verified method call is inside verify() where it should be on the outside:
2878      * verify(mock.execute());
2879      *
2880      * //Oops, missing method to verify:
2881      * verify(mock);
2882      * </code></pre>
2883      *
2884      * Mockito throws exceptions if you misuse it so that you know if your tests are written correctly.
2885      * The gotcha is that Mockito does the validation <b>next time</b> you use the framework (e.g. next time you verify, stub, call mock etc.).
2886      * But even though the exception might be thrown in the next test,
2887      * the exception <b>message contains a navigable stack trace element</b> with location of the defect.
2888      * Hence you can click and find the place where Mockito was misused.
2889      * <p>
2890      * Sometimes though, you might want to validate the framework usage explicitly.
2891      * For example, one of the users wanted to put <code>validateMockitoUsage()</code> in his <code>&#064;After</code> method
2892      * so that he knows immediately when he misused Mockito.
2893      * Without it, he would have known about it not sooner than <b>next time</b> he used the framework.
2894      * One more benefit of having <code>validateMockitoUsage()</code> in <code>&#064;After</code> is that jUnit runner and rule will always fail in the test method with defect
2895      * whereas ordinary 'next-time' validation might fail the <b>next</b> test method.
2896      * But even though JUnit might report next test as red, don't worry about it
2897      * and just click at navigable stack trace element in the exception message to instantly locate the place where you misused mockito.
2898      * <p>
2899      * <b>Both built-in runner: {@link MockitoJUnitRunner} and rule: {@link MockitoRule}</b> do validateMockitoUsage() after each test method.
2900      * <p>
2901      * Bear in mind that <b>usually you don't have to <code>validateMockitoUsage()</code></b>
2902      * and framework validation triggered on next-time basis should be just enough,
2903      * mainly because of enhanced exception message with clickable location of defect.
2904      * However, I would recommend validateMockitoUsage() if you already have sufficient test infrastructure
2905      * (like your own runner or base class for all tests) because adding a special action to <code>&#064;After</code> has zero cost.
2906      * <p>
2907      * See examples in javadoc for {@link Mockito} class
2908      */
validateMockitoUsage()2909     public static void validateMockitoUsage() {
2910         MOCKITO_CORE.validateMockitoUsage();
2911     }
2912 
2913     /**
2914      * Allows mock creation with additional mock settings.
2915      * <p>
2916      * Don't use it too often.
2917      * Consider writing simple tests that use simple mocks.
2918      * Repeat after me: simple tests push simple, KISSy, readable & maintainable code.
2919      * If you cannot write a test in a simple way - refactor the code under test.
2920      * <p>
2921      * Examples of mock settings:
2922      * <pre class="code"><code class="java">
2923      *   //Creates mock with different default answer & name
2924      *   Foo mock = mock(Foo.class, withSettings()
2925      *       .defaultAnswer(RETURNS_SMART_NULLS)
2926      *       .name("cool mockie"));
2927      *
2928      *   //Creates mock with different default answer, descriptive name and extra interfaces
2929      *   Foo mock = mock(Foo.class, withSettings()
2930      *       .defaultAnswer(RETURNS_SMART_NULLS)
2931      *       .name("cool mockie")
2932      *       .extraInterfaces(Bar.class));
2933      * </code></pre>
2934      * {@link MockSettings} has been introduced for two reasons.
2935      * Firstly, to make it easy to add another mock settings when the demand comes.
2936      * Secondly, to enable combining different mock settings without introducing zillions of overloaded mock() methods.
2937      * <p>
2938      * See javadoc for {@link MockSettings} to learn about possible mock settings.
2939      * <p>
2940      *
2941      * @return mock settings instance with defaults.
2942      */
2943     @CheckReturnValue
withSettings()2944     public static MockSettings withSettings() {
2945         return new MockSettingsImpl().defaultAnswer(RETURNS_DEFAULTS);
2946     }
2947 
2948     /**
2949      * Adds a description to be printed if verification fails.
2950      * <pre class="code"><code class="java">
2951      * verify(mock, description("This will print on failure")).someMethod("some arg");
2952      * </code></pre>
2953      * @param description The description to print on failure.
2954      * @return verification mode
2955      * @since 2.1.0
2956      */
2957     @CheckReturnValue
description(String description)2958     public static VerificationMode description(String description) {
2959         return times(1).description(description);
2960     }
2961 
2962     /**
2963      * @deprecated - please use {@link MockingDetails#printInvocations()} instead.
2964      * An instance of {@code MockingDetails} can be retrieved via {@link #mockingDetails(Object)}.
2965      */
2966     @Deprecated
2967     @CheckReturnValue
debug()2968     static MockitoDebugger debug() {
2969         return new MockitoDebuggerImpl();
2970     }
2971 
2972     /**
2973      * For advanced users or framework integrators. See {@link MockitoFramework} class.
2974      *
2975      * @since 2.1.0
2976      */
2977     @Incubating
2978     @CheckReturnValue
framework()2979     public static MockitoFramework framework() {
2980         return new DefaultMockitoFramework();
2981     }
2982 
2983     /**
2984      * {@code MockitoSession} is an optional, highly recommended feature
2985      * that helps driving cleaner tests by eliminating boilerplate code and adding extra validation.
2986      * <p>
2987      * For more information, including use cases and sample code, see the javadoc for {@link MockitoSession}.
2988      *
2989      * @since 2.7.0
2990      */
2991     @Incubating
2992     @CheckReturnValue
mockitoSession()2993     public static MockitoSessionBuilder mockitoSession() {
2994         return new DefaultMockitoSessionBuilder();
2995     }
2996 
2997     /**
2998      * Lenient stubs bypass "strict stubbing" validation (see {@link Strictness#STRICT_STUBS}).
2999      * When stubbing is declared as lenient, it will not be checked for potential stubbing problems such as
3000      * 'unnecessary stubbing' ({@link UnnecessaryStubbingException}) or for 'stubbing argument mismatch' {@link PotentialStubbingProblem}.
3001      *
3002      * <pre class="code"><code class="java">
3003      *   lenient().when(mock.foo()).thenReturn("ok");
3004      * </code></pre>
3005      *
3006      * Most mocks in most tests don't need leniency and should happily prosper with {@link Strictness#STRICT_STUBS}.
3007      * <ul>
3008      *     <li>If a specific stubbing needs to be lenient - use this method</li>
3009      *     <li>If a specific mock need to have stubbings lenient - use {@link MockSettings#lenient()}</li>
3010      *     <li>If a specific test method / test class needs to have all stubbings lenient
3011      *          - configure strictness using our JUnit support ({@link MockitoJUnit} or Mockito Session ({@link MockitoSession})</li>
3012      *
3013      * <h3>Elaborate example</h3>
3014      *
3015      * In below example, 'foo.foo()' is a stubbing that was moved to 'before()' method to avoid duplication.
3016      * Doing so makes one of the test methods ('test3()') fail with 'unnecessary stubbing'.
3017      * To resolve it we can configure 'foo.foo()' stubbing in 'before()' method to be lenient.
3018      * Alternatively, we can configure entire 'foo' mock as lenient.
3019      * <p>
3020      * This example is simplified and not realistic.
3021      * Pushing stubbings to 'before()' method may cause tests to be less readable.
3022      * Some repetition in tests is OK, use your own judgement to write great tests!
3023      * It is not desired to eliminate all possible duplication from the test code
3024      * because it may add complexity and conceal important test information.
3025      *
3026      * <pre class="code"><code class="java">
3027      * public class SomeTest {
3028      *
3029      *     &#064;Rule public MockitoRule mockito = MockitoJUnit.rule().strictness(STRICT_STUBS);
3030      *
3031      *     &#064;Mock Foo foo;
3032      *     &#064;Mock Bar bar;
3033      *
3034      *     &#064;Before public void before() {
3035      *         when(foo.foo()).thenReturn("ok");
3036      *
3037      *         // it is better to configure the stubbing to be lenient:
3038      *         // lenient().when(foo.foo()).thenReturn("ok");
3039      *
3040      *         // or the entire mock to be lenient:
3041      *         // foo = mock(Foo.class, withSettings().lenient());
3042      *     }
3043      *
3044      *     &#064;Test public void test1() {
3045      *         foo.foo();
3046      *     }
3047      *
3048      *     &#064;Test public void test2() {
3049      *         foo.foo();
3050      *     }
3051      *
3052      *     &#064;Test public void test3() {
3053      *         bar.bar();
3054      *     }
3055      * }
3056      * </code></pre>
3057      *
3058      * @since 2.20.0
3059      */
3060     @Incubating
lenient()3061     public static LenientStubber lenient() {
3062         return MOCKITO_CORE.lenient();
3063     }
3064 }
3065