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      1 /*
      2 **********************************************************************
      3 *   Copyright (C) 1999-2010, International Business Machines
      4 *   Corporation and others.  All Rights Reserved.
      5 **********************************************************************
      6 */
      7 
      8 //
      9 //  UVector64 is a class implementing a vector of 64 bit integers.
     10 //            It is similar to UVector32, but holds int64_t values rather than int32_t.
     11 //            Most of the code is unchanged from UVector.
     12 //
     13 
     14 #ifndef UVECTOR64_H
     15 #define UVECTOR64_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 an <tt>int64_t</tt> vector
     28  * that has a subset of methods from UVector32
     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  */
     58 class U_COMMON_API UVector64 : public UObject {
     59 private:
     60     int32_t   count;
     61 
     62     int32_t   capacity;
     63 
     64     int32_t   maxCapacity;   // Limit beyond which capacity is not permitted to grow.
     65 
     66     int64_t*  elements;
     67 
     68 public:
     69     UVector64(UErrorCode &status);
     70 
     71     UVector64(int32_t initialCapacity, UErrorCode &status);
     72 
     73     virtual ~UVector64();
     74 
     75     /**
     76      * Assign this object to another (make this a copy of 'other').
     77      * Use the 'assign' function to assign each element.
     78      */
     79     void assign(const UVector64& other, UErrorCode &ec);
     80 
     81     /**
     82      * Compare this vector with another.  They will be considered
     83      * equal if they are of the same size and all elements are equal,
     84      * as compared using this object's comparer.
     85      */
     86     UBool operator==(const UVector64& other);
     87 
     88     /**
     89      * Equivalent to !operator==()
     90      */
     91     inline UBool operator!=(const UVector64& other);
     92 
     93     //------------------------------------------------------------
     94     // subset of java.util.Vector API
     95     //------------------------------------------------------------
     96 
     97     void addElement(int64_t elem, UErrorCode &status);
     98 
     99     void setElementAt(int64_t elem, int32_t index);
    100 
    101     void insertElementAt(int64_t elem, int32_t index, UErrorCode &status);
    102 
    103     int64_t elementAti(int32_t index) const;
    104 
    105     //UBool equals(const UVector64 &other) const;
    106 
    107     int64_t lastElementi(void) const;
    108 
    109     //int32_t indexOf(int64_t elem, int32_t startIndex = 0) const;
    110 
    111     //UBool contains(int64_t elem) const;
    112 
    113     //UBool containsAll(const UVector64& other) const;
    114 
    115     //UBool removeAll(const UVector64& other);
    116 
    117     //UBool retainAll(const UVector64& other);
    118 
    119     //void removeElementAt(int32_t index);
    120 
    121     void removeAllElements();
    122 
    123     int32_t size(void) const;
    124 
    125     //UBool isEmpty(void) const;
    126 
    127     // Inline.  Use this one for speedy size check.
    128     inline UBool ensureCapacity(int32_t minimumCapacity, UErrorCode &status);
    129 
    130     // Out-of-line, handles actual growth.  Called by ensureCapacity() when necessary.
    131     UBool expandCapacity(int32_t minimumCapacity, UErrorCode &status);
    132 
    133     /**
    134      * Change the size of this vector as follows: If newSize is
    135      * smaller, then truncate the array, possibly deleting held
    136      * elements for i >= newSize.  If newSize is larger, grow the
    137      * array, filling in new slows with zero.
    138      */
    139     void setSize(int32_t newSize);
    140 
    141     //------------------------------------------------------------
    142     // New API
    143     //------------------------------------------------------------
    144 
    145     //UBool containsNone(const UVector64& other) const;
    146 
    147 
    148     //void sortedInsert(int64_t elem, UErrorCode& ec);
    149 
    150     /**
    151      * Returns a pointer to the internal array holding the vector.
    152      */
    153     int64_t *getBuffer() const;
    154 
    155     /**
    156      * Set the maximum allowed buffer capacity for this vector/stack.
    157      * Default with no limit set is unlimited, go until malloc() fails.
    158      * A Limit of zero means unlimited capacity.
    159      * Units are vector elements (64 bits each), not bytes.
    160      */
    161     void setMaxCapacity(int32_t limit);
    162 
    163     /**
    164      * ICU "poor man's RTTI", returns a UClassID for this class.
    165      */
    166     static UClassID U_EXPORT2 getStaticClassID();
    167 
    168     /**
    169      * ICU "poor man's RTTI", returns a UClassID for the actual class.
    170      */
    171     virtual UClassID getDynamicClassID() const;
    172 
    173 private:
    174     void _init(int32_t initialCapacity, UErrorCode &status);
    175 
    176     // Disallow
    177     UVector64(const UVector64&);
    178 
    179     // Disallow
    180     UVector64& operator=(const UVector64&);
    181 
    182 
    183     //  API Functions for Stack operations.
    184     //  In the original UVector, these were in a separate derived class, UStack.
    185     //  Here in UVector64, they are all together.
    186 public:
    187     //UBool empty(void) const;   // TODO:  redundant, same as empty().  Remove it?
    188 
    189     //int64_t peeki(void) const;
    190 
    191     int64_t popi(void);
    192 
    193     int64_t push(int64_t i, UErrorCode &status);
    194 
    195     int64_t *reserveBlock(int32_t size, UErrorCode &status);
    196     int64_t *popFrame(int32_t size);
    197 };
    198 
    199 
    200 // UVector64 inlines
    201 
    202 inline UBool UVector64::ensureCapacity(int32_t minimumCapacity, UErrorCode &status) {
    203     if ((minimumCapacity >= 0) && (capacity >= minimumCapacity)) {
    204         return TRUE;
    205     } else {
    206         return expandCapacity(minimumCapacity, status);
    207     }
    208 }
    209 
    210 inline int64_t UVector64::elementAti(int32_t index) const {
    211     return (0 <= index && index < count) ? elements[index] : 0;
    212 }
    213 
    214 
    215 inline void UVector64::addElement(int64_t elem, UErrorCode &status) {
    216     if (ensureCapacity(count + 1, status)) {
    217         elements[count] = elem;
    218         count++;
    219     }
    220 }
    221 
    222 inline int64_t *UVector64::reserveBlock(int32_t size, UErrorCode &status) {
    223     if (ensureCapacity(count+size, status) == FALSE) {
    224         return NULL;
    225     }
    226     int64_t  *rp = elements+count;
    227     count += size;
    228     return rp;
    229 }
    230 
    231 inline int64_t *UVector64::popFrame(int32_t size) {
    232     U_ASSERT(count >= size);
    233     count -= size;
    234     if (count < 0) {
    235         count = 0;
    236     }
    237     return elements+count-size;
    238 }
    239 
    240 
    241 
    242 inline int32_t UVector64::size(void) const {
    243     return count;
    244 }
    245 
    246 inline int64_t UVector64::lastElementi(void) const {
    247     return elementAti(count-1);
    248 }
    249 
    250 inline UBool UVector64::operator!=(const UVector64& other) {
    251     return !operator==(other);
    252 }
    253 
    254 inline int64_t *UVector64::getBuffer() const {
    255     return elements;
    256 }
    257 
    258 
    259 // UStack inlines
    260 
    261 inline int64_t UVector64::push(int64_t i, UErrorCode &status) {
    262     addElement(i, status);
    263     return i;
    264 }
    265 
    266 inline int64_t UVector64::popi(void) {
    267     int64_t result = 0;
    268     if (count > 0) {
    269         count--;
    270         result = elements[count];
    271     }
    272     return result;
    273 }
    274 
    275 U_NAMESPACE_END
    276 
    277 #endif
    278