refhash2keystableof.c

来自「IBM的解析xml的工具Xerces的源代码」· C语言 代码 · 共 578 行 · 第 1/2 页

/*
 * Copyright 2001,2004 The Apache Software Foundation.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * $Log: RefHash2KeysTableOf.c,v $
 * Revision 1.11  2004/09/22 11:14:22  amassari
 * Reorder initialization of variables in constructor
 *
 * Revision 1.10  2004/09/08 13:56:22  peiyongz
 * Apache License Version 2.0
 *
 * Revision 1.9  2004/08/30 18:56:20  amassari
 * Change the order of testing to save some CPU cycles
 *
 * Revision 1.8  2004/08/30 15:18:35  amassari
 * - Added transferElement API
 * - The iterator class now can iterate over the items having the same primary key
 *
 * Revision 1.7  2004/03/01 15:03:08  peiyongz
 * new getter: getHashModulus
 *
 * Revision 1.6  2003/12/17 00:18:35  cargilld
 * Update to memory management so that the static memory manager (one used to call Initialize) is only for static data.
 *
 * Revision 1.5  2003/10/17 21:10:40  peiyongz
 * nextElementKey() added
 *
 * Revision 1.4  2003/05/18 14:02:05  knoaman
 * Memory manager implementation: pass per instance manager.
 *
 * Revision 1.3  2003/05/15 19:04:35  knoaman
 * Partial implementation of the configurable memory manager.
 *
 * Revision 1.2  2002/11/04 15:22:04  tng
 * C++ Namespace Support.
 *
 * Revision 1.1.1.1  2002/02/01 22:22:12  peiyongz
 * sane_include
 *
 * Revision 1.5  2001/07/19 18:43:18  peiyongz
 * fix: detect null poiniter in enumerator's ctor.
 *
 * Revision 1.4  2001/06/04 13:45:03  tng
 * The "hash" argument clashes with STL hash.  Fixed by Pei Yong Zhang.
 *
 * Revision 1.3  2001/05/11 13:26:28  tng
 * Copyright update.
 *
 * Revision 1.2  2001/03/14 13:18:21  tng
 * typo: should use fKey1
 *
 * Revision 1.1  2001/02/27 18:24:00  tng
 * Schema: Add utility RefHash2KeysTableOf.
 *
 */


// ---------------------------------------------------------------------------
//  Include
// ---------------------------------------------------------------------------
#if defined(XERCES_TMPLSINC)
#include <xercesc/util/RefHash2KeysTableOf.hpp>
#endif

#include <xercesc/util/NullPointerException.hpp>

XERCES_CPP_NAMESPACE_BEGIN

// ---------------------------------------------------------------------------
//  RefHash2KeysTableOf: Constructors and Destructor
// ---------------------------------------------------------------------------
template <class TVal>
RefHash2KeysTableOf<TVal>::RefHash2KeysTableOf( const unsigned int   modulus
                                              , const bool           adoptElems
                                              , MemoryManager* const manager)
    : fMemoryManager(manager)
	, fAdoptedElems(adoptElems)
    , fBucketList(0)
    , fHashModulus(modulus)
    , fHash(0)
{
    initialize(modulus);
	
	// create default hasher
	fHash = new (fMemoryManager) HashXMLCh();
}

template <class TVal>
RefHash2KeysTableOf<TVal>::RefHash2KeysTableOf( const unsigned int   modulus
                                              , const bool           adoptElems
                                              , HashBase*            hashBase
                                              , MemoryManager* const manager)
	: fMemoryManager(manager)
    , fAdoptedElems(adoptElems)
    , fBucketList(0)
    , fHashModulus(modulus)
    , fHash(0)
{
	initialize(modulus);
	// set hasher
	fHash = hashBase;
}

template <class TVal>
RefHash2KeysTableOf<TVal>::RefHash2KeysTableOf(const unsigned int modulus,
                                               MemoryManager* const manager)
	: fMemoryManager(manager)
    , fAdoptedElems(true)
    , fBucketList(0)
    , fHashModulus(modulus)
    , fHash(0)
{
	initialize(modulus);

	// create default hasher
	fHash = new (fMemoryManager) HashXMLCh();
}

template <class TVal>
void RefHash2KeysTableOf<TVal>::initialize(const unsigned int modulus)
{
	if (modulus == 0)
        ThrowXMLwithMemMgr(IllegalArgumentException, XMLExcepts::HshTbl_ZeroModulus, fMemoryManager);

    // Allocate the bucket list and zero them
    fBucketList = (RefHash2KeysTableBucketElem<TVal>**) fMemoryManager->allocate
    (
        fHashModulus * sizeof(RefHash2KeysTableBucketElem<TVal>*)
    ); //new RefHash2KeysTableBucketElem<TVal>*[fHashModulus];
    for (unsigned int index = 0; index < fHashModulus; index++)
        fBucketList[index] = 0;
}

template <class TVal> RefHash2KeysTableOf<TVal>::~RefHash2KeysTableOf()
{
    removeAll();

    // Then delete the bucket list & hasher
    fMemoryManager->deallocate(fBucketList); //delete [] fBucketList;
	delete fHash;
}


// ---------------------------------------------------------------------------
//  RefHash2KeysTableOf: Element management
// ---------------------------------------------------------------------------
template <class TVal> bool RefHash2KeysTableOf<TVal>::isEmpty() const
{
    // Just check the bucket list for non-empty elements
    for (unsigned int buckInd = 0; buckInd < fHashModulus; buckInd++)
    {
        if (fBucketList[buckInd] != 0)
            return false;
    }
    return true;
}

template <class TVal> bool RefHash2KeysTableOf<TVal>::
containsKey(const void* const key1, const int key2) const
{
    unsigned int hashVal;
    const RefHash2KeysTableBucketElem<TVal>* findIt = findBucketElem(key1, key2, hashVal);
    return (findIt != 0);
}

template <class TVal> void RefHash2KeysTableOf<TVal>::
removeKey(const void* const key1, const int key2)
{
    unsigned int hashVal;
    removeBucketElem(key1, key2, hashVal);
}

template <class TVal> void RefHash2KeysTableOf<TVal>::removeAll()
{
    // Clean up the buckets first
    for (unsigned int buckInd = 0; buckInd < fHashModulus; buckInd++)
    {
        // Get the bucket list head for this entry
        RefHash2KeysTableBucketElem<TVal>* curElem = fBucketList[buckInd];
        RefHash2KeysTableBucketElem<TVal>* nextElem;
        while (curElem)
        {
            // Save the next element before we hose this one
            nextElem = curElem->fNext;

            // If we adopted the data, then delete it too
            //    (Note:  the userdata hash table instance has data type of void *.
            //    This will generate compiler warnings here on some platforms, but they
            //    can be ignored since fAdoptedElements is false.
            if (fAdoptedElems)
                delete curElem->fData;

            // Then delete the current element and move forward
            delete curElem;
            curElem = nextElem;
        }

        // Clean out this entry
        fBucketList[buckInd] = 0;
    }
}

// this function transfer the data from key1 to key2
template <class TVal> void RefHash2KeysTableOf<TVal>::transferElement(const void* const key1, void* key2)
{
    // Hash the key
    unsigned int hashVal = fHash->getHashVal(key1, fHashModulus);
    if (hashVal > fHashModulus)
        ThrowXMLwithMemMgr(RuntimeException, XMLExcepts::HshTbl_BadHashFromKey, fMemoryManager);

    //
    //  Search the given bucket for this key. Keep up with the previous
    //  element so we can patch around it.
    //
    RefHash2KeysTableBucketElem<TVal>* curElem = fBucketList[hashVal];
    RefHash2KeysTableBucketElem<TVal>* lastElem = 0;

    while (curElem)
    {
        // if this element has the same primary key, remove it and add it using the new primary key
        if (fHash->equals(key1, curElem->fKey1))
        {
            if (!lastElem)
            {
                // It was the first in the bucket
                fBucketList[hashVal] = curElem->fNext;
            }
            else
            {
                // Patch around the current element
                lastElem->fNext = curElem->fNext;
            }

            put(key2, curElem->fKey2, curElem->fData);

            RefHash2KeysTableBucketElem<TVal>* elemToDelete = curElem;
            
            // Update just curElem; lastElem must stay the same
            curElem = curElem->fNext;

            // Delete the current element
            delete elemToDelete;
        }
        else
        {
            // Move both pointers upwards
            lastElem = curElem;
            curElem = curElem->fNext;
        }
    }
}



// ---------------------------------------------------------------------------
//  RefHash2KeysTableOf: Getters
// ---------------------------------------------------------------------------
template <class TVal> TVal* RefHash2KeysTableOf<TVal>::get(const void* const key1, const int key2)
{
    unsigned int hashVal;
    RefHash2KeysTableBucketElem<TVal>* findIt = findBucketElem(key1, key2, hashVal);
    if (!findIt)
        return 0;
    return findIt->fData;
}

template <class TVal> const TVal* RefHash2KeysTableOf<TVal>::
get(const void* const key1, const int key2) const
{
    unsigned int hashVal;
    const RefHash2KeysTableBucketElem<TVal>* findIt = findBucketElem(key1, key2, hashVal);
    if (!findIt)
        return 0;
    return findIt->fData;
}