refhashtableof.c

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



// this function transfer the data from key1 to key2
// this is equivalent to calling
//  1.  get(key1) to retrieve the data,
//  2.  removeKey(key1),
//  3.  and then put(key2, data)
// except that the data is not deleted in "removeKey" even it is adopted so that it
// can be transferred to key2.
// whatever key2 has originally will be purged (if adopted)
template <class TElem> void RefHashTableOf<TElem>::transferElement(const void* const key1, void* key2)
{
    put(key2, orphanKey(key1));
}


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

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

template <class TVal>
MemoryManager* RefHashTableOf<TVal>::getMemoryManager() const
{
    return fMemoryManager;
}


// ---------------------------------------------------------------------------
//  RefHashTableOf: Getters
// ---------------------------------------------------------------------------
template <class TVal>
void RefHashTableOf<TVal>::setAdoptElements(const bool aValue)
{
    fAdoptedElems = aValue;
}

// ---------------------------------------------------------------------------
//  RefHashTableOf: Putters
// ---------------------------------------------------------------------------
template <class TVal> void RefHashTableOf<TVal>::put(void* key, TVal* const valueToAdopt)
{
    // Apply 0.75 load factor to find threshold.
    unsigned int threshold = fHashModulus * 3 / 4;
    
    // If we've grown too big, expand the table and rehash.
    if (fCount >= threshold)
        rehash();

    // First see if the key exists already
    unsigned int hashVal;
    RefHashTableBucketElem<TVal>* newBucket = findBucketElem(key, hashVal);

    //
    //  If so,then update its value. If not, then we need to add it to
    //  the right bucket
    //
    if (newBucket)
    {
        if (fAdoptedElems)
            delete newBucket->fData;
        newBucket->fData = valueToAdopt;
		newBucket->fKey = key;
    }
     else
    {
        newBucket = new (fMemoryManager) RefHashTableBucketElem<TVal>(key, valueToAdopt, fBucketList[hashVal]);
        fBucketList[hashVal] = newBucket;
    }

    fCount++;
}



// ---------------------------------------------------------------------------
//  RefHashTableOf: Private methods
// ---------------------------------------------------------------------------
template <class TVal> void RefHashTableOf<TVal>::rehash()
{
    unsigned int index;
    unsigned int oldMod = fHashModulus;
    fHashModulus *= 2;
    
    RefHashTableBucketElem<TVal>** oldBucketList = fBucketList;
    
    fBucketList = (RefHashTableBucketElem<TVal>**) fMemoryManager->allocate
    (
        fHashModulus * sizeof(RefHashTableBucketElem<TVal>*)
    );//new RefHashTableBucketElem<TVal>*[fHashModulus];
    for (index = 0; index < fHashModulus; index++)
        fBucketList[index] = 0;
    
    
    // Rehash all existing entries.
    for (index = 0; index < oldMod; index++)
    {
        // Get the bucket list head for this entry
        RefHashTableBucketElem<TVal>* curElem = oldBucketList[index];
        RefHashTableBucketElem<TVal>* nextElem;
        while (curElem)
        {
            // Save the next element before we detach this one
            nextElem = curElem->fNext;

            unsigned int hashVal = fHash->getHashVal(curElem->fKey, fHashModulus, fMemoryManager);
            if (hashVal > fHashModulus)
                ThrowXMLwithMemMgr(RuntimeException, XMLExcepts::HshTbl_BadHashFromKey, fMemoryManager);
            
            RefHashTableBucketElem<TVal>* newHeadElem = fBucketList[hashVal];
            
            // Insert at the start of this bucket's list.
            curElem->fNext = newHeadElem;
            fBucketList[hashVal] = curElem;
            
            curElem = nextElem;
        }
    }
            
    fMemoryManager->deallocate(oldBucketList);//delete[] oldBucketList;
    
}

template <class TVal> RefHashTableBucketElem<TVal>* RefHashTableOf<TVal>::
findBucketElem(const void* const key, unsigned int& hashVal)
{
    // Hash the key
    hashVal = fHash->getHashVal(key, fHashModulus, fMemoryManager);
    if (hashVal > fHashModulus)
        ThrowXMLwithMemMgr(RuntimeException, XMLExcepts::HshTbl_BadHashFromKey, fMemoryManager);

    // Search that bucket for the key
    RefHashTableBucketElem<TVal>* curElem = fBucketList[hashVal];
    while (curElem)
    {
		if (fHash->equals(key, curElem->fKey))
            return curElem;

        curElem = curElem->fNext;
    }
    return 0;
}

template <class TVal> const RefHashTableBucketElem<TVal>* RefHashTableOf<TVal>::
findBucketElem(const void* const key, unsigned int& hashVal) const
{
    // Hash the key
    hashVal = fHash->getHashVal(key, fHashModulus, fMemoryManager);
    if (hashVal > fHashModulus)
        ThrowXMLwithMemMgr(RuntimeException, XMLExcepts::HshTbl_BadHashFromKey, fMemoryManager);

    // Search that bucket for the key
    const RefHashTableBucketElem<TVal>* curElem = fBucketList[hashVal];
    while (curElem)
    {
        if (fHash->equals(key, curElem->fKey))
            return curElem;

        curElem = curElem->fNext;
    }
    return 0;
}


template <class TVal> void RefHashTableOf<TVal>::
removeBucketElem(const void* const key, unsigned int& hashVal)
{
    // Hash the key
    hashVal = fHash->getHashVal(key, fHashModulus, fMemoryManager);
    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.
    //
    RefHashTableBucketElem<TVal>* curElem = fBucketList[hashVal];
    RefHashTableBucketElem<TVal>* lastElem = 0;

    while (curElem)
    {
        if (fHash->equals(key, curElem->fKey))
        {
            if (!lastElem)
            {
                // It was the first in the bucket
                fBucketList[hashVal] = curElem->fNext;
            }
             else
            {
                // Patch around the current element
                lastElem->fNext = curElem->fNext;
            }

            // If we adopted the elements, then delete the data
            if (fAdoptedElems)
                delete curElem->fData;

            // Delete the current element
            delete curElem;

            fCount--;

            return;
        }

        // Move both pointers upwards
        lastElem = curElem;
        curElem = curElem->fNext;
    }

    // We never found that key
    ThrowXMLwithMemMgr(NoSuchElementException, XMLExcepts::HshTbl_NoSuchKeyExists, fMemoryManager);
}



// ---------------------------------------------------------------------------
//  RefHashTableOfEnumerator: Constructors and Destructor
// ---------------------------------------------------------------------------
template <class TVal> RefHashTableOfEnumerator<TVal>::
RefHashTableOfEnumerator(RefHashTableOf<TVal>* const toEnum
                         , const bool adopt
                         , MemoryManager* const manager)
	: fAdopted(adopt), fCurElem(0), fCurHash((unsigned int)-1), fToEnum(toEnum)
    , fMemoryManager(manager)
{
    if (!toEnum)
        ThrowXMLwithMemMgr(NullPointerException, XMLExcepts::CPtr_PointerIsZero, fMemoryManager);

    //
    //  Find the next available bucket element in the hash table. If it
    //  comes back zero, that just means the table is empty.
    //
    //  Note that the -1 in the current hash tells it to start from the
    //  beginning.
    //
    findNext();
}

template <class TVal> RefHashTableOfEnumerator<TVal>::~RefHashTableOfEnumerator()
{
    if (fAdopted)
        delete fToEnum;
}


template <class TVal> RefHashTableOfEnumerator<TVal>::
RefHashTableOfEnumerator(const RefHashTableOfEnumerator<TVal>& toCopy) :
    fAdopted(toCopy.fAdopted)
    , fCurElem(toCopy.fCurElem)
    , fCurHash(toCopy.fCurHash)
    , fToEnum(toCopy.fToEnum)
    , fMemoryManager(toCopy.fMemoryManager)
{
}
// ---------------------------------------------------------------------------
//  RefHashTableOfEnumerator: Enum interface
// ---------------------------------------------------------------------------
template <class TVal> bool RefHashTableOfEnumerator<TVal>::hasMoreElements() const
{
    //
    //  If our current has is at the max and there are no more elements
    //  in the current bucket, then no more elements.
    //
    if (!fCurElem && (fCurHash == fToEnum->fHashModulus))
        return false;
    return true;
}

template <class TVal> TVal& RefHashTableOfEnumerator<TVal>::nextElement()
{
    // Make sure we have an element to return
    if (!hasMoreElements())
        ThrowXMLwithMemMgr(NoSuchElementException, XMLExcepts::Enum_NoMoreElements, fMemoryManager);

    //
    //  Save the current element, then move up to the next one for the
    //  next time around.
    //
    RefHashTableBucketElem<TVal>* saveElem = fCurElem;
    findNext();

    return *saveElem->fData;
}

template <class TVal> void* RefHashTableOfEnumerator<TVal>::nextElementKey()
{
    // Make sure we have an element to return
    if (!hasMoreElements())
        ThrowXMLwithMemMgr(NoSuchElementException, XMLExcepts::Enum_NoMoreElements, fMemoryManager);

    //
    //  Save the current element, then move up to the next one for the
    //  next time around.
    //
    RefHashTableBucketElem<TVal>* saveElem = fCurElem;
    findNext();

    return saveElem->fKey;
}

template <class TVal> void RefHashTableOfEnumerator<TVal>::Reset()
{
    fCurHash = (unsigned int)-1;
    fCurElem = 0;
    findNext();
}



// ---------------------------------------------------------------------------
//  RefHashTableOfEnumerator: Private helper methods
// ---------------------------------------------------------------------------
template <class TVal> void RefHashTableOfEnumerator<TVal>::findNext()
{
    //
    //  If there is a current element, move to its next element. If this
    //  hits the end of the bucket, the next block will handle the rest.
    //
    if (fCurElem)
        fCurElem = fCurElem->fNext;

    //
    //  If the current element is null, then we have to move up to the
    //  next hash value. If that is the hash modulus, then we cannot
    //  go further.
    //
    if (!fCurElem)
    {
        fCurHash++;
        if (fCurHash == fToEnum->fHashModulus)
            return;

        // Else find the next non-empty bucket
        while (true)
        {
            if (fToEnum->fBucketList[fCurHash])
                break;

            // Bump to the next hash value. If we max out return
            fCurHash++;
            if (fCurHash == fToEnum->fHashModulus)
                return;
        }
        fCurElem = fToEnum->fBucketList[fCurHash];
    }
}

XERCES_CPP_NAMESPACE_END