1 /*
2 **********************************************************************
3 *   Copyright (C) 1999-2011, International Business Machines
4 *   Corporation and others.  All Rights Reserved.
5 **********************************************************************
6 */
7 
8 //
9 //  UVector32 is a class implementing a vector of 32 bit integers.
10 //            It is similar to UVector, but holds int32_t values rather than pointers.
11 //            Most of the code is unchanged from UVector.
12 //
13 
14 #ifndef UVECTOR32_H
15 #define UVECTOR32_H
16 
17 #include "unicode/utypes.h"
18 #include "unicode/uobject.h"
19 #include "uhash.h"
20 #include "uassert.h"
21 
22 U_NAMESPACE_BEGIN
23 
24 
25 
26 /**
27  * <p>Ultralightweight C++ implementation of a <tt>void*</tt> vector
28  * that is (mostly) compatible with java.util.Vector.
29  *
30  * <p>This is a very simple implementation, written to satisfy an
31  * immediate porting need.  As such, it is not completely fleshed out,
32  * and it aims for simplicity and conformity.  Nonetheless, it serves
33  * its purpose (porting code from java that uses java.util.Vector)
34  * well, and it could be easily made into a more robust vector class.
35  *
36  * <p><b>Design notes</b>
37  *
38  * <p>There is index bounds checking, but little is done about it.  If
39  * indices are out of bounds, either nothing happens, or zero is
40  * returned.  We <em>do</em> avoid indexing off into the weeds.
41  *
42  * <p>There is detection of out of memory, but the handling is very
43  * coarse-grained -- similar to UnicodeString's protocol, but even
44  * coarser.  The class contains <em>one static flag</em> that is set
45  * when any call to <tt>new</tt> returns zero.  This allows the caller
46  * to use several vectors and make just one check at the end to see if
47  * a memory failure occurred.  This is more efficient than making a
48  * check after each call on each vector when doing many operations on
49  * multiple vectors.  The single static flag works best when memory
50  * failures are infrequent, and when recovery options are limited or
51  * nonexistent.
52  *
53  * <p><b>To do</b>
54  *
55  * <p>Improve the handling of index out of bounds errors.
56  *
57  * @author Alan Liu
58  */
59 class U_COMMON_API UVector32 : public UObject {
60 private:
61     int32_t   count;
62 
63     int32_t   capacity;
64 
65     int32_t   maxCapacity;   // Limit beyond which capacity is not permitted to grow.
66 
67     int32_t*  elements;
68 
69 public:
70     UVector32(UErrorCode &status);
71 
72     UVector32(int32_t initialCapacity, UErrorCode &status);
73 
74     virtual ~UVector32();
75 
76     /**
77      * Assign this object to another (make this a copy of 'other').
78      * Use the 'assign' function to assign each element.
79      */
80     void assign(const UVector32& other, UErrorCode &ec);
81 
82     /**
83      * Compare this vector with another.  They will be considered
84      * equal if they are of the same size and all elements are equal,
85      * as compared using this object's comparer.
86      */
87     UBool operator==(const UVector32& other);
88 
89     /**
90      * Equivalent to !operator==()
91      */
92     inline UBool operator!=(const UVector32& other);
93 
94     //------------------------------------------------------------
95     // java.util.Vector API
96     //------------------------------------------------------------
97 
98     void addElement(int32_t elem, UErrorCode &status);
99 
100     void setElementAt(int32_t elem, int32_t index);
101 
102     void insertElementAt(int32_t elem, int32_t index, UErrorCode &status);
103 
104     int32_t elementAti(int32_t index) const;
105 
106     UBool equals(const UVector32 &other) const;
107 
108     int32_t lastElementi(void) const;
109 
110     int32_t indexOf(int32_t elem, int32_t startIndex = 0) const;
111 
112     UBool contains(int32_t elem) const;
113 
114     UBool containsAll(const UVector32& other) const;
115 
116     UBool removeAll(const UVector32& other);
117 
118     UBool retainAll(const UVector32& other);
119 
120     void removeElementAt(int32_t index);
121 
122     void removeAllElements();
123 
124     int32_t size(void) const;
125 
126     UBool isEmpty(void) const;
127 
128     // Inline.  Use this one for speedy size check.
129     inline UBool ensureCapacity(int32_t minimumCapacity, UErrorCode &status);
130 
131     // Out-of-line, handles actual growth.  Called by ensureCapacity() when necessary.
132     UBool expandCapacity(int32_t minimumCapacity, UErrorCode &status);
133 
134     /**
135      * Change the size of this vector as follows: If newSize is
136      * smaller, then truncate the array, possibly deleting held
137      * elements for i >= newSize.  If newSize is larger, grow the
138      * array, filling in new slows with zero.
139      */
140     void setSize(int32_t newSize);
141 
142     //------------------------------------------------------------
143     // New API
144     //------------------------------------------------------------
145 
146     /**
147      * Returns true if this vector contains none of the elements
148      * of the given vector.
149      * @param other vector to be checked for containment
150      * @return true if the test condition is met
151      */
152     UBool containsNone(const UVector32& other) const;
153 
154 
155     /**
156      * Insert the given integer into this vector at its sorted position.
157      * The current elements are assumed to be sorted already.
158      */
159     void sortedInsert(int32_t elem, UErrorCode& ec);
160 
161     /**
162      * Returns a pointer to the internal array holding the vector.
163      */
164     int32_t *getBuffer() const;
165 
166     /**
167      * Set the maximum allowed buffer capacity for this vector/stack.
168      * Default with no limit set is unlimited, go until malloc() fails.
169      * A Limit of zero means unlimited capacity.
170      * Units are vector elements (32 bits each), not bytes.
171      */
172     void setMaxCapacity(int32_t limit);
173 
174     /**
175      * ICU "poor man's RTTI", returns a UClassID for this class.
176      */
177     static UClassID U_EXPORT2 getStaticClassID();
178 
179     /**
180      * ICU "poor man's RTTI", returns a UClassID for the actual class.
181      */
182     virtual UClassID getDynamicClassID() const;
183 
184 private:
185     void _init(int32_t initialCapacity, UErrorCode &status);
186 
187     // Disallow
188     UVector32(const UVector32&);
189 
190     // Disallow
191     UVector32& operator=(const UVector32&);
192 
193 
194     //  API Functions for Stack operations.
195     //  In the original UVector, these were in a separate derived class, UStack.
196     //  Here in UVector32, they are all together.
197 public:
198     UBool empty(void) const;   // TODO:  redundant, same as empty().  Remove it?
199 
200     int32_t peeki(void) const;
201 
202     int32_t popi(void);
203 
204     int32_t push(int32_t i, UErrorCode &status);
205 
206     int32_t *reserveBlock(int32_t size, UErrorCode &status);
207     int32_t *popFrame(int32_t size);
208 };
209 
210 
211 // UVector32 inlines
212 
ensureCapacity(int32_t minimumCapacity,UErrorCode & status)213 inline UBool UVector32::ensureCapacity(int32_t minimumCapacity, UErrorCode &status) {
214     if ((minimumCapacity >= 0) && (capacity >= minimumCapacity)) {
215         return TRUE;
216     } else {
217         return expandCapacity(minimumCapacity, status);
218     }
219 }
220 
elementAti(int32_t index)221 inline int32_t UVector32::elementAti(int32_t index) const {
222     return (index >= 0 && count > 0 && count - index > 0) ? elements[index] : 0;
223 }
224 
225 
addElement(int32_t elem,UErrorCode & status)226 inline void UVector32::addElement(int32_t elem, UErrorCode &status) {
227     if (ensureCapacity(count + 1, status)) {
228         elements[count] = elem;
229         count++;
230     }
231 }
232 
reserveBlock(int32_t size,UErrorCode & status)233 inline int32_t *UVector32::reserveBlock(int32_t size, UErrorCode &status) {
234     if (ensureCapacity(count+size, status) == FALSE) {
235         return NULL;
236     }
237     int32_t  *rp = elements+count;
238     count += size;
239     return rp;
240 }
241 
popFrame(int32_t size)242 inline int32_t *UVector32::popFrame(int32_t size) {
243     U_ASSERT(count >= size);
244     count -= size;
245     if (count < 0) {
246         count = 0;
247     }
248     return elements+count-size;
249 }
250 
251 
252 
size(void)253 inline int32_t UVector32::size(void) const {
254     return count;
255 }
256 
isEmpty(void)257 inline UBool UVector32::isEmpty(void) const {
258     return count == 0;
259 }
260 
contains(int32_t obj)261 inline UBool UVector32::contains(int32_t obj) const {
262     return indexOf(obj) >= 0;
263 }
264 
lastElementi(void)265 inline int32_t UVector32::lastElementi(void) const {
266     return elementAti(count-1);
267 }
268 
269 inline UBool UVector32::operator!=(const UVector32& other) {
270     return !operator==(other);
271 }
272 
getBuffer()273 inline int32_t *UVector32::getBuffer() const {
274     return elements;
275 }
276 
277 
278 // UStack inlines
279 
empty(void)280 inline UBool UVector32::empty(void) const {
281     return isEmpty();
282 }
283 
peeki(void)284 inline int32_t UVector32::peeki(void) const {
285     return lastElementi();
286 }
287 
push(int32_t i,UErrorCode & status)288 inline int32_t UVector32::push(int32_t i, UErrorCode &status) {
289     addElement(i, status);
290     return i;
291 }
292 
popi(void)293 inline int32_t UVector32::popi(void) {
294     int32_t result = 0;
295     if (count > 0) {
296         count--;
297         result = elements[count];
298     }
299     return result;
300 }
301 
302 U_NAMESPACE_END
303 
304 #endif
305