1 /*
2 **********************************************************************
3 *   Copyright (C) 1999-2013, International Business Machines
4 *   Corporation and others.  All Rights Reserved.
5 **********************************************************************
6 *   Date        Name        Description
7 *   10/22/99    alan        Creation.  This is an internal header.
8 *                           It should not be exported.
9 **********************************************************************
10 */
11 
12 #ifndef UVECTOR_H
13 #define UVECTOR_H
14 
15 #include "unicode/utypes.h"
16 #include "unicode/uobject.h"
17 #include "cmemory.h"
18 #include "uarrsort.h"
19 #include "uelement.h"
20 
21 U_NAMESPACE_BEGIN
22 
23 /**
24  * <p>Ultralightweight C++ implementation of a <tt>void*</tt> vector
25  * that is (mostly) compatible with java.util.Vector.
26  *
27  * <p>This is a very simple implementation, written to satisfy an
28  * immediate porting need.  As such, it is not completely fleshed out,
29  * and it aims for simplicity and conformity.  Nonetheless, it serves
30  * its purpose (porting code from java that uses java.util.Vector)
31  * well, and it could be easily made into a more robust vector class.
32  *
33  * <p><b>Design notes</b>
34  *
35  * <p>There is index bounds checking, but little is done about it.  If
36  * indices are out of bounds, either nothing happens, or zero is
37  * returned.  We <em>do</em> avoid indexing off into the weeds.
38  *
39  * <p>There is detection of out of memory, but the handling is very
40  * coarse-grained -- similar to UnicodeString's protocol, but even
41  * coarser.  The class contains <em>one static flag</em> that is set
42  * when any call to <tt>new</tt> returns zero.  This allows the caller
43  * to use several vectors and make just one check at the end to see if
44  * a memory failure occurred.  This is more efficient than making a
45  * check after each call on each vector when doing many operations on
46  * multiple vectors.  The single static flag works best when memory
47  * failures are infrequent, and when recovery options are limited or
48  * nonexistent.
49  *
50  * <p>Since we don't have garbage collection, UVector was given the
51  * option to <em>own</em>its contents.  To employ this, set a deleter
52  * function.  The deleter is called on a void* pointer when that
53  * pointer is released by the vector, either when the vector itself is
54  * destructed, or when a call to setElementAt() overwrites an element,
55  * or when a call to remove() or one of its variants explicitly
56  * removes an element.  If no deleter is set, or the deleter is set to
57  * zero, then it is assumed that the caller will delete elements as
58  * needed.
59  *
60  * <p>In order to implement methods such as contains() and indexOf(),
61  * UVector needs a way to compare objects for equality.  To do so, it
62  * uses a comparison frunction, or "comparer."  If the comparer is not
63  * set, or is set to zero, then all such methods will act as if the
64  * vector contains no element.  That is, indexOf() will always return
65  * -1, contains() will always return FALSE, etc.
66  *
67  * <p><b>To do</b>
68  *
69  * <p>Improve the handling of index out of bounds errors.
70  *
71  * @author Alan Liu
72  */
73 class U_COMMON_API UVector : public UObject {
74     // NOTE: UVector uses the UHashKey (union of void* and int32_t) as
75     // its basic storage type.  It uses UElementsAreEqual as its
76     // comparison function.  It uses UObjectDeleter as its deleter
77     // function.  These are named for hashtables, but used here as-is
78     // rather than duplicating the type.  This allows sharing of
79     // support functions.
80 
81 private:
82     int32_t count;
83 
84     int32_t capacity;
85 
86     UElement* elements;
87 
88     UObjectDeleter *deleter;
89 
90     UElementsAreEqual *comparer;
91 
92 public:
93     UVector(UErrorCode &status);
94 
95     UVector(int32_t initialCapacity, UErrorCode &status);
96 
97     UVector(UObjectDeleter *d, UElementsAreEqual *c, UErrorCode &status);
98 
99     UVector(UObjectDeleter *d, UElementsAreEqual *c, int32_t initialCapacity, UErrorCode &status);
100 
101     virtual ~UVector();
102 
103     /**
104      * Assign this object to another (make this a copy of 'other').
105      * Use the 'assign' function to assign each element.
106      */
107     void assign(const UVector& other, UElementAssigner *assign, UErrorCode &ec);
108 
109     /**
110      * Compare this vector with another.  They will be considered
111      * equal if they are of the same size and all elements are equal,
112      * as compared using this object's comparer.
113      */
114     UBool operator==(const UVector& other);
115 
116     /**
117      * Equivalent to !operator==()
118      */
119     inline UBool operator!=(const UVector& other);
120 
121     //------------------------------------------------------------
122     // java.util.Vector API
123     //------------------------------------------------------------
124 
125     void addElement(void* obj, UErrorCode &status);
126 
127     void addElement(int32_t elem, UErrorCode &status);
128 
129     void setElementAt(void* obj, int32_t index);
130 
131     void setElementAt(int32_t elem, int32_t index);
132 
133     void insertElementAt(void* obj, int32_t index, UErrorCode &status);
134 
135     void insertElementAt(int32_t elem, int32_t index, UErrorCode &status);
136 
137     void* elementAt(int32_t index) const;
138 
139     int32_t elementAti(int32_t index) const;
140 
141     UBool equals(const UVector &other) const;
142 
143     void* firstElement(void) const;
144 
145     void* lastElement(void) const;
146 
147     int32_t lastElementi(void) const;
148 
149     int32_t indexOf(void* obj, int32_t startIndex = 0) const;
150 
151     int32_t indexOf(int32_t obj, int32_t startIndex = 0) const;
152 
153     UBool contains(void* obj) const;
154 
155     UBool contains(int32_t obj) const;
156 
157     UBool containsAll(const UVector& other) const;
158 
159     UBool removeAll(const UVector& other);
160 
161     UBool retainAll(const UVector& other);
162 
163     void removeElementAt(int32_t index);
164 
165     UBool removeElement(void* obj);
166 
167     void removeAllElements();
168 
169     int32_t size(void) const;
170 
171     UBool isEmpty(void) const;
172 
173     UBool ensureCapacity(int32_t minimumCapacity, UErrorCode &status);
174 
175     /**
176      * Change the size of this vector as follows: If newSize is
177      * smaller, then truncate the array, possibly deleting held
178      * elements for i >= newSize.  If newSize is larger, grow the
179      * array, filling in new slots with NULL.
180      */
181     void setSize(int32_t newSize, UErrorCode &status);
182 
183     /**
184      * Fill in the given array with all elements of this vector.
185      */
186     void** toArray(void** result) const;
187 
188     //------------------------------------------------------------
189     // New API
190     //------------------------------------------------------------
191 
192     UObjectDeleter *setDeleter(UObjectDeleter *d);
193 
194     UElementsAreEqual *setComparer(UElementsAreEqual *c);
195 
196     void* operator[](int32_t index) const;
197 
198     /**
199      * Removes the element at the given index from this vector and
200      * transfer ownership of it to the caller.  After this call, the
201      * caller owns the result and must delete it and the vector entry
202      * at 'index' is removed, shifting all subsequent entries back by
203      * one index and shortening the size of the vector by one.  If the
204      * index is out of range or if there is no item at the given index
205      * then 0 is returned and the vector is unchanged.
206      */
207     void* orphanElementAt(int32_t index);
208 
209     /**
210      * Returns true if this vector contains none of the elements
211      * of the given vector.
212      * @param other vector to be checked for containment
213      * @return true if the test condition is met
214      */
215     UBool containsNone(const UVector& other) const;
216 
217     /**
218      * Insert the given object into this vector at its sorted position
219      * as defined by 'compare'.  The current elements are assumed to
220      * be sorted already.
221      */
222     void sortedInsert(void* obj, UElementComparator *compare, UErrorCode& ec);
223 
224     /**
225      * Insert the given integer into this vector at its sorted position
226      * as defined by 'compare'.  The current elements are assumed to
227      * be sorted already.
228      */
229     void sortedInsert(int32_t obj, UElementComparator *compare, UErrorCode& ec);
230 
231     /**
232      * Sort the contents of the vector, assuming that the contents of the
233      * vector are of type int32_t.
234      */
235     void sorti(UErrorCode &ec);
236 
237     /**
238       * Sort the contents of this vector, using a caller-supplied function
239       * to do the comparisons.  (It's confusing that
240       *  UVector's UElementComparator function is different from the
241       *  UComparator function type defined in uarrsort.h)
242       */
243     void sort(UElementComparator *compare, UErrorCode &ec);
244 
245     /**
246      * Stable sort the contents of this vector using a caller-supplied function
247      * of type UComparator to do the comparison.  Provides more flexibility
248      * than UVector::sort() because an additional user parameter can be passed to
249      * the comparison function.
250      */
251     void sortWithUComparator(UComparator *compare, const void *context, UErrorCode &ec);
252 
253     /**
254      * ICU "poor man's RTTI", returns a UClassID for this class.
255      */
256     static UClassID U_EXPORT2 getStaticClassID();
257 
258     /**
259      * ICU "poor man's RTTI", returns a UClassID for the actual class.
260      */
261     virtual UClassID getDynamicClassID() const;
262 
263 private:
264     void _init(int32_t initialCapacity, UErrorCode &status);
265 
266     int32_t indexOf(UElement key, int32_t startIndex = 0, int8_t hint = 0) const;
267 
268     void sortedInsert(UElement e, UElementComparator *compare, UErrorCode& ec);
269 
270     // Disallow
271     UVector(const UVector&);
272 
273     // Disallow
274     UVector& operator=(const UVector&);
275 
276 };
277 
278 
279 /**
280  * <p>Ultralightweight C++ implementation of a <tt>void*</tt> stack
281  * that is (mostly) compatible with java.util.Stack.  As in java, this
282  * is merely a paper thin layer around UVector.  See the UVector
283  * documentation for further information.
284  *
285  * <p><b>Design notes</b>
286  *
287  * <p>The element at index <tt>n-1</tt> is (of course) the top of the
288  * stack.
289  *
290  * <p>The poorly named <tt>empty()</tt> method doesn't empty the
291  * stack; it determines if the stack is empty.
292  *
293  * @author Alan Liu
294  */
295 class U_COMMON_API UStack : public UVector {
296 public:
297     UStack(UErrorCode &status);
298 
299     UStack(int32_t initialCapacity, UErrorCode &status);
300 
301     UStack(UObjectDeleter *d, UElementsAreEqual *c, UErrorCode &status);
302 
303     UStack(UObjectDeleter *d, UElementsAreEqual *c, int32_t initialCapacity, UErrorCode &status);
304 
305     virtual ~UStack();
306 
307     // It's okay not to have a virtual destructor (in UVector)
308     // because UStack has no special cleanup to do.
309 
310     UBool empty(void) const;
311 
312     void* peek(void) const;
313 
314     int32_t peeki(void) const;
315 
316     void* pop(void);
317 
318     int32_t popi(void);
319 
320     void* push(void* obj, UErrorCode &status);
321 
322     int32_t push(int32_t i, UErrorCode &status);
323 
324     /*
325     If the object o occurs as an item in this stack,
326     this method returns the 1-based distance from the top of the stack.
327     */
328     int32_t search(void* obj) const;
329 
330     /**
331      * ICU "poor man's RTTI", returns a UClassID for this class.
332      */
333     static UClassID U_EXPORT2 getStaticClassID();
334 
335     /**
336      * ICU "poor man's RTTI", returns a UClassID for the actual class.
337      */
338     virtual UClassID getDynamicClassID() const;
339 
340 private:
341     // Disallow
342     UStack(const UStack&);
343 
344     // Disallow
345     UStack& operator=(const UStack&);
346 };
347 
348 
349 // UVector inlines
350 
size(void)351 inline int32_t UVector::size(void) const {
352     return count;
353 }
354 
isEmpty(void)355 inline UBool UVector::isEmpty(void) const {
356     return count == 0;
357 }
358 
contains(void * obj)359 inline UBool UVector::contains(void* obj) const {
360     return indexOf(obj) >= 0;
361 }
362 
contains(int32_t obj)363 inline UBool UVector::contains(int32_t obj) const {
364     return indexOf(obj) >= 0;
365 }
366 
firstElement(void)367 inline void* UVector::firstElement(void) const {
368     return elementAt(0);
369 }
370 
lastElement(void)371 inline void* UVector::lastElement(void) const {
372     return elementAt(count-1);
373 }
374 
lastElementi(void)375 inline int32_t UVector::lastElementi(void) const {
376     return elementAti(count-1);
377 }
378 
379 inline void* UVector::operator[](int32_t index) const {
380     return elementAt(index);
381 }
382 
383 inline UBool UVector::operator!=(const UVector& other) {
384     return !operator==(other);
385 }
386 
387 // UStack inlines
388 
empty(void)389 inline UBool UStack::empty(void) const {
390     return isEmpty();
391 }
392 
peek(void)393 inline void* UStack::peek(void) const {
394     return lastElement();
395 }
396 
peeki(void)397 inline int32_t UStack::peeki(void) const {
398     return lastElementi();
399 }
400 
push(void * obj,UErrorCode & status)401 inline void* UStack::push(void* obj, UErrorCode &status) {
402     addElement(obj, status);
403     return obj;
404 }
405 
push(int32_t i,UErrorCode & status)406 inline int32_t UStack::push(int32_t i, UErrorCode &status) {
407     addElement(i, status);
408     return i;
409 }
410 
411 U_NAMESPACE_END
412 
413 #endif
414