1 /*
2  * Copyright (C) 2013 The Guava Authors
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
5  * in compliance with the License. You may obtain a copy of the License at
6  *
7  * http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software distributed under the License
10  * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
11  * or implied. See the License for the specific language governing permissions and limitations under
12  * the License.
13  */
14 
15 package com.google.common.collect.testing.testers;
16 
17 import static com.google.common.collect.testing.features.CollectionSize.ONE;
18 import static com.google.common.collect.testing.features.CollectionSize.ZERO;
19 import static com.google.common.collect.testing.features.MapFeature.ALLOWS_NULL_KEYS;
20 import static com.google.common.collect.testing.features.MapFeature.ALLOWS_NULL_VALUES;
21 
22 import com.google.common.annotations.GwtCompatible;
23 import com.google.common.collect.testing.AbstractMapTester;
24 import com.google.common.collect.testing.features.CollectionSize;
25 import com.google.common.collect.testing.features.MapFeature;
26 
27 import java.util.LinkedHashMap;
28 import java.util.Map;
29 import java.util.Map.Entry;
30 import java.util.Set;
31 
32 /**
33  * A generic JUnit test which tests {@code toString()} operations on a map. Can't be invoked
34  * directly; please see {@link com.google.common.collect.testing.MapTestSuiteBuilder}.
35  *
36  * @author Kevin Bourrillion
37  * @author Louis Wasserman
38  */
39 @GwtCompatible
40 public class MapToStringTester<K, V> extends AbstractMapTester<K, V> {
testToString_minimal()41   public void testToString_minimal() {
42     assertNotNull("toString() should not return null", getMap().toString());
43   }
44 
45   @CollectionSize.Require(ZERO)
testToString_size0()46   public void testToString_size0() {
47     assertEquals("emptyMap.toString should return {}", "{}", getMap().toString());
48   }
49 
50   @CollectionSize.Require(ONE)
testToString_size1()51   public void testToString_size1() {
52     assertEquals(
53         "size1Map.toString should return {entry}", "{" + samples.e0 + "}", getMap().toString());
54   }
55 
56   @CollectionSize.Require(absent = ZERO)
57   @MapFeature.Require(ALLOWS_NULL_KEYS)
testToStringWithNullKey()58   public void testToStringWithNullKey() {
59     initMapWithNullKey();
60     testToString_formatting();
61   }
62 
63   @CollectionSize.Require(absent = ZERO)
64   @MapFeature.Require(ALLOWS_NULL_VALUES)
testToStringWithNullValue()65   public void testToStringWithNullValue() {
66     initMapWithNullValue();
67     testToString_formatting();
68   }
69 
testToString_formatting()70   public void testToString_formatting() {
71     assertEquals(
72         "map.toString() incorrect", expectedToString(getMap().entrySet()), getMap().toString());
73   }
74 
expectedToString(Set<Entry<K, V>> entries)75   private String expectedToString(Set<Entry<K, V>> entries) {
76     Map<K, V> reference = new LinkedHashMap<K, V>();
77     for (Map.Entry<K, V> entry : entries) {
78       reference.put(entry.getKey(), entry.getValue());
79     }
80     return reference.toString();
81   }
82 }
83