icuSources/common/uvector.h

   1 // © 2016 and later: Unicode, Inc. and others.
   2 // License & terms of use: http://www.unicode.org/copyright.html
   3 /*
   4 **********************************************************************
   5 *   Copyright (C) 1999-2016, International Business Machines
   6 *   Corporation and others.  All Rights Reserved.
   7 **********************************************************************
   8 *   Date        Name        Description
   9 *   10/22/99    alan        Creation.  This is an internal header.
  10 *                           It should not be exported.
  11 **********************************************************************
  12 */
  13
  14 #ifndef UVECTOR_H
  15 #define UVECTOR_H
  16
  17 #include "unicode/utypes.h"
  18 #include "unicode/uobject.h"
  19 #include "cmemory.h"
  20 #include "uarrsort.h"
  21 #include "uelement.h"
  22
  23 U_NAMESPACE_BEGIN
  24
  25 /**
  26  * <p>Ultralightweight C++ implementation of a <tt>void*</tt> vector
  27  * that is (mostly) compatible with java.util.Vector.
  28  *
  29  * <p>This is a very simple implementation, written to satisfy an
  30  * immediate porting need.  As such, it is not completely fleshed out,
  31  * and it aims for simplicity and conformity.  Nonetheless, it serves
  32  * its purpose (porting code from java that uses java.util.Vector)
  33  * well, and it could be easily made into a more robust vector class.
  34  *
  35  * <p><b>Design notes</b>
  36  *
  37  * <p>There is index bounds checking, but little is done about it.  If
  38  * indices are out of bounds, either nothing happens, or zero is
  39  * returned.  We <em>do</em> avoid indexing off into the weeds.
  40  *
  41  * <p>There is detection of out of memory, but the handling is very
  42  * coarse-grained -- similar to UnicodeString's protocol, but even
  43  * coarser.  The class contains <em>one static flag</em> that is set
  44  * when any call to <tt>new</tt> returns zero.  This allows the caller
  45  * to use several vectors and make just one check at the end to see if
  46  * a memory failure occurred.  This is more efficient than making a
  47  * check after each call on each vector when doing many operations on
  48  * multiple vectors.  The single static flag works best when memory
  49  * failures are infrequent, and when recovery options are limited or
  50  * nonexistent.
  51  *
  52  * <p>Since we don't have garbage collection, UVector was given the
  53  * option to <em>own</em>its contents.  To employ this, set a deleter
  54  * function.  The deleter is called on a void* pointer when that
  55  * pointer is released by the vector, either when the vector itself is
  56  * destructed, or when a call to setElementAt() overwrites an element,
  57  * or when a call to remove() or one of its variants explicitly
  58  * removes an element.  If no deleter is set, or the deleter is set to
  59  * zero, then it is assumed that the caller will delete elements as
  60  * needed.
  61  *
  62  * <p>In order to implement methods such as contains() and indexOf(),
  63  * UVector needs a way to compare objects for equality.  To do so, it
  64  * uses a comparison function, or "comparer."  If the comparer is not
  65  * set, or is set to zero, then all such methods will act as if the
  66  * vector contains no element.  That is, indexOf() will always return
  67  * -1, contains() will always return FALSE, etc.
  68  *
  69  * <p><b>To do</b>
  70  *
  71  * <p>Improve the handling of index out of bounds errors.
  72  *
  73  * @author Alan Liu
  74  */
  75 class U_COMMON_API UVector : public UObject {
  76     // NOTE: UVector uses the UHashKey (union of void* and int32_t) as
  77     // its basic storage type.  It uses UElementsAreEqual as its
  78     // comparison function.  It uses UObjectDeleter as its deleter
  79     // function.  These are named for hashtables, but used here as-is
  80     // rather than duplicating the type.  This allows sharing of
  81     // support functions.
  82
  83 private:
  84     int32_t count;
  85
  86     int32_t capacity;
  87
  88     UElement* elements;
  89
  90     UObjectDeleter *deleter;
  91
  92     UElementsAreEqual *comparer;
  93
  94 public:
  95     UVector(UErrorCode &status);
  96
  97     UVector(int32_t initialCapacity, UErrorCode &status);
  98
  99     UVector(UObjectDeleter *d, UElementsAreEqual *c, UErrorCode &status);
 100
 101     UVector(UObjectDeleter *d, UElementsAreEqual *c, int32_t initialCapacity, UErrorCode &status);
 102
 103     virtual ~UVector();
 104
 105     /**
 106      * Assign this object to another (make this a copy of 'other').
 107      * Use the 'assign' function to assign each element.
 108      */
 109     void assign(const UVector& other, UElementAssigner *assign, UErrorCode &ec);
 110
 111     /**
 112      * Compare this vector with another.  They will be considered
 113      * equal if they are of the same size and all elements are equal,
 114      * as compared using this object's comparer.
 115      */
 116     UBool operator==(const UVector& other);
 117
 118     /**
 119      * Equivalent to !operator==()
 120      */
 121     inline UBool operator!=(const UVector& other);
 122
 123     //------------------------------------------------------------
 124     // java.util.Vector API
 125     //------------------------------------------------------------
 126
 127     void addElement(void* obj, UErrorCode &status);
 128
 129     void addElement(int32_t elem, UErrorCode &status);
 130
 131     void setElementAt(void* obj, int32_t index);
 132
 133     void setElementAt(int32_t elem, int32_t index);
 134
 135     void insertElementAt(void* obj, int32_t index, UErrorCode &status);
 136
 137     void insertElementAt(int32_t elem, int32_t index, UErrorCode &status);
 138
 139     void* elementAt(int32_t index) const;
 140
 141     int32_t elementAti(int32_t index) const;
 142
 143     UBool equals(const UVector &other) const;
 144
 145     inline void* firstElement(void) const;
 146
 147     inline void* lastElement(void) const;
 148
 149     inline int32_t lastElementi(void) const;
 150
 151     int32_t indexOf(void* obj, int32_t startIndex = 0) const;
 152
 153     int32_t indexOf(int32_t obj, int32_t startIndex = 0) const;
 154
 155     inline UBool contains(void* obj) const;
 156
 157     inline UBool contains(int32_t obj) const;
 158
 159     UBool containsAll(const UVector& other) const;
 160
 161     UBool removeAll(const UVector& other);
 162
 163     UBool retainAll(const UVector& other);
 164
 165     void removeElementAt(int32_t index);
 166
 167     UBool removeElement(void* obj);
 168
 169     void removeAllElements();
 170
 171     inline int32_t size(void) const;
 172
 173     inline UBool isEmpty(void) const;
 174
 175     UBool ensureCapacity(int32_t minimumCapacity, UErrorCode &status);
 176
 177     /**
 178      * Change the size of this vector as follows: If newSize is
 179      * smaller, then truncate the array, possibly deleting held
 180      * elements for i >= newSize.  If newSize is larger, grow the
 181      * array, filling in new slots with NULL.
 182      */
 183     void setSize(int32_t newSize, UErrorCode &status);
 184
 185     /**
 186      * Fill in the given array with all elements of this vector.
 187      */
 188     void** toArray(void** result) const;
 189
 190     //------------------------------------------------------------
 191     // New API
 192     //------------------------------------------------------------
 193
 194     UObjectDeleter *setDeleter(UObjectDeleter *d);
 195
 196     UElementsAreEqual *setComparer(UElementsAreEqual *c);
 197
 198     inline void* operator[](int32_t index) const;
 199
 200     /**
 201      * Removes the element at the given index from this vector and
 202      * transfer ownership of it to the caller.  After this call, the
 203      * caller owns the result and must delete it and the vector entry
 204      * at 'index' is removed, shifting all subsequent entries back by
 205      * one index and shortening the size of the vector by one.  If the
 206      * index is out of range or if there is no item at the given index
 207      * then 0 is returned and the vector is unchanged.
 208      */
 209     void* orphanElementAt(int32_t index);
 210
 211     /**
 212      * Returns true if this vector contains none of the elements
 213      * of the given vector.
 214      * @param other vector to be checked for containment
 215      * @return true if the test condition is met
 216      */
 217     UBool containsNone(const UVector& other) const;
 218
 219     /**
 220      * Insert the given object into this vector at its sorted position
 221      * as defined by 'compare'.  The current elements are assumed to
 222      * be sorted already.
 223      */
 224     void sortedInsert(void* obj, UElementComparator *compare, UErrorCode& ec);
 225
 226     /**
 227      * Insert the given integer into this vector at its sorted position
 228      * as defined by 'compare'.  The current elements are assumed to
 229      * be sorted already.
 230      */
 231     void sortedInsert(int32_t obj, UElementComparator *compare, UErrorCode& ec);
 232
 233     /**
 234      * Sort the contents of the vector, assuming that the contents of the
 235      * vector are of type int32_t.
 236      */
 237     void sorti(UErrorCode &ec);
 238
 239     /**
 240       * Sort the contents of this vector, using a caller-supplied function
 241       * to do the comparisons.  (It's confusing that
 242       *  UVector's UElementComparator function is different from the
 243       *  UComparator function type defined in uarrsort.h)
 244       */
 245     void sort(UElementComparator *compare, UErrorCode &ec);
 246
 247     /**
 248      * Stable sort the contents of this vector using a caller-supplied function
 249      * of type UComparator to do the comparison.  Provides more flexibility
 250      * than UVector::sort() because an additional user parameter can be passed to
 251      * the comparison function.
 252      */
 253     void sortWithUComparator(UComparator *compare, const void *context, UErrorCode &ec);
 254
 255     /**
 256      * ICU "poor man's RTTI", returns a UClassID for this class.
 257      */
 258     static UClassID U_EXPORT2 getStaticClassID();
 259
 260     /**
 261      * ICU "poor man's RTTI", returns a UClassID for the actual class.
 262      */
 263     virtual UClassID getDynamicClassID() const;
 264
 265 private:
 266     void _init(int32_t initialCapacity, UErrorCode &status);
 267
 268     int32_t indexOf(UElement key, int32_t startIndex = 0, int8_t hint = 0) const;
 269
 270     void sortedInsert(UElement e, UElementComparator *compare, UErrorCode& ec);
 271
 272     // Disallow
 273     UVector(const UVector&);
 274
 275     // Disallow
 276     UVector& operator=(const UVector&);
 277
 278 };
 279
 280
 281 /**
 282  * <p>Ultralightweight C++ implementation of a <tt>void*</tt> stack
 283  * that is (mostly) compatible with java.util.Stack.  As in java, this
 284  * is merely a paper thin layer around UVector.  See the UVector
 285  * documentation for further information.
 286  *
 287  * <p><b>Design notes</b>
 288  *
 289  * <p>The element at index <tt>n-1</tt> is (of course) the top of the
 290  * stack.
 291  *
 292  * <p>The poorly named <tt>empty()</tt> method doesn't empty the
 293  * stack; it determines if the stack is empty.
 294  *
 295  * @author Alan Liu
 296  */
 297 class U_COMMON_API UStack : public UVector {
 298 public:
 299     UStack(UErrorCode &status);
 300
 301     UStack(int32_t initialCapacity, UErrorCode &status);
 302
 303     UStack(UObjectDeleter *d, UElementsAreEqual *c, UErrorCode &status);
 304
 305     UStack(UObjectDeleter *d, UElementsAreEqual *c, int32_t initialCapacity, UErrorCode &status);
 306
 307     virtual ~UStack();
 308
 309     // It's okay not to have a virtual destructor (in UVector)
 310     // because UStack has no special cleanup to do.
 311
 312     inline UBool empty(void) const;
 313
 314     inline void* peek(void) const;
 315
 316     inline int32_t peeki(void) const;
 317
 318     void* pop(void);
 319
 320     int32_t popi(void);
 321
 322     inline void* push(void* obj, UErrorCode &status);
 323
 324     inline int32_t push(int32_t i, UErrorCode &status);
 325
 326     /*
 327     If the object o occurs as an item in this stack,
 328     this method returns the 1-based distance from the top of the stack.
 329     */
 330     int32_t search(void* obj) const;
 331
 332     /**
 333      * ICU "poor man's RTTI", returns a UClassID for this class.
 334      */
 335     static UClassID U_EXPORT2 getStaticClassID();
 336
 337     /**
 338      * ICU "poor man's RTTI", returns a UClassID for the actual class.
 339      */
 340     virtual UClassID getDynamicClassID() const;
 341
 342 private:
 343     // Disallow
 344     UStack(const UStack&);
 345
 346     // Disallow
 347     UStack& operator=(const UStack&);
 348 };
 349
 350
 351 // UVector inlines
 352
 353 inline int32_t UVector::size(void) const {
 354     return count;
 355 }
 356
 357 inline UBool UVector::isEmpty(void) const {
 358     return count == 0;
 359 }
 360
 361 inline UBool UVector::contains(void* obj) const {
 362     return indexOf(obj) >= 0;
 363 }
 364
 365 inline UBool UVector::contains(int32_t obj) const {
 366     return indexOf(obj) >= 0;
 367 }
 368
 369 inline void* UVector::firstElement(void) const {
 370     return elementAt(0);
 371 }
 372
 373 inline void* UVector::lastElement(void) const {
 374     return elementAt(count-1);
 375 }
 376
 377 inline int32_t UVector::lastElementi(void) const {
 378     return elementAti(count-1);
 379 }
 380
 381 inline void* UVector::operator[](int32_t index) const {
 382     return elementAt(index);
 383 }
 384
 385 inline UBool UVector::operator!=(const UVector& other) {
 386     return !operator==(other);
 387 }
 388
 389 // UStack inlines
 390
 391 inline UBool UStack::empty(void) const {
 392     return isEmpty();
 393 }
 394
 395 inline void* UStack::peek(void) const {
 396     return lastElement();
 397 }
 398
 399 inline int32_t UStack::peeki(void) const {
 400     return lastElementi();
 401 }
 402
 403 inline void* UStack::push(void* obj, UErrorCode &status) {
 404     addElement(obj, status);
 405     return obj;
 406 }
 407
 408 inline int32_t UStack::push(int32_t i, UErrorCode &status) {
 409     addElement(i, status);
 410     return i;
 411 }
 412
 413 U_NAMESPACE_END
 414
 415 #endif