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

template <class TVal>
MemoryManager* RefHash2KeysTableOf<TVal>::getMemoryManager() const
{
    return fMemoryManager;
}

template <class TVal>
unsigned int RefHash2KeysTableOf<TVal>::getHashModulus() const
{
    return fHashModulus;
}

// ---------------------------------------------------------------------------
//  RefHash2KeysTableOf: Putters
// ---------------------------------------------------------------------------
template <class TVal> void RefHash2KeysTableOf<TVal>::put(void* key1, int key2, TVal* const valueToAdopt)
{
    // First see if the key exists already
    unsigned int hashVal;
    RefHash2KeysTableBucketElem<TVal>* newBucket = findBucketElem(key1, key2, 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->fKey1 = key1;
		newBucket->fKey2 = key2;
    }
     else
    {
        newBucket = new (fMemoryManager) RefHash2KeysTableBucketElem<TVal>(key1, key2, valueToAdopt, fBucketList[hashVal]);
        fBucketList[hashVal] = newBucket;
    }
}



// ---------------------------------------------------------------------------
//  RefHash2KeysTableOf: Private methods
// ---------------------------------------------------------------------------
template <class TVal> RefHash2KeysTableBucketElem<TVal>* RefHash2KeysTableOf<TVal>::
findBucketElem(const void* const key1, const int key2, unsigned int& hashVal)
{
    // Hash the key
    hashVal = fHash->getHashVal(key1, fHashModulus, fMemoryManager);
    if (hashVal > fHashModulus)
        ThrowXMLwithMemMgr(RuntimeException, XMLExcepts::HshTbl_BadHashFromKey, fMemoryManager);

    // Search that bucket for the key
    RefHash2KeysTableBucketElem<TVal>* curElem = fBucketList[hashVal];
    while (curElem)
    {
		if (key2==curElem->fKey2 && fHash->equals(key1, curElem->fKey1))
            return curElem;

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

template <class TVal> const RefHash2KeysTableBucketElem<TVal>* RefHash2KeysTableOf<TVal>::
findBucketElem(const void* const key1, const int key2, unsigned int& hashVal) const
{
    // Hash the key
    hashVal = fHash->getHashVal(key1, fHashModulus, fMemoryManager);
    if (hashVal > fHashModulus)
        ThrowXMLwithMemMgr(RuntimeException, XMLExcepts::HshTbl_BadHashFromKey, fMemoryManager);

    // Search that bucket for the key
    const RefHash2KeysTableBucketElem<TVal>* curElem = fBucketList[hashVal];
    while (curElem)
    {
        if (fHash->equals(key1, curElem->fKey1) && (key2==curElem->fKey2))
            return curElem;

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


template <class TVal> void RefHash2KeysTableOf<TVal>::
removeBucketElem(const void* const key1, const int key2, unsigned int& hashVal)
{
    // Hash the key
    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 (fHash->equals(key1, curElem->fKey1) && (key2==curElem->fKey2))
        {
            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;

            return;
        }

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

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




// ---------------------------------------------------------------------------
//  RefHash2KeysTableOfEnumerator: Constructors and Destructor
// ---------------------------------------------------------------------------
template <class TVal> RefHash2KeysTableOfEnumerator<TVal>::
RefHash2KeysTableOfEnumerator(RefHash2KeysTableOf<TVal>* const toEnum
                              , const bool adopt
                              , MemoryManager* const manager)
	: fAdopted(adopt), fCurElem(0), fCurHash((unsigned int)-1), fToEnum(toEnum)
    , fMemoryManager(manager)
    , fLockPrimaryKey(0)
{
    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> RefHash2KeysTableOfEnumerator<TVal>::~RefHash2KeysTableOfEnumerator()
{
    if (fAdopted)
        delete fToEnum;
}


// ---------------------------------------------------------------------------
//  RefHash2KeysTableOfEnumerator: Enum interface
// ---------------------------------------------------------------------------
template <class TVal> bool RefHash2KeysTableOfEnumerator<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& RefHash2KeysTableOfEnumerator<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.
    //
    RefHash2KeysTableBucketElem<TVal>* saveElem = fCurElem;
    findNext();

    return *saveElem->fData;
}

template <class TVal> void RefHash2KeysTableOfEnumerator<TVal>::nextElementKey(void*& retKey1, int& retKey2)
{
    // 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.
    //
    RefHash2KeysTableBucketElem<TVal>* saveElem = fCurElem;
    findNext();

    retKey1 = saveElem->fKey1;
    retKey2 = saveElem->fKey2;

    return;
}

template <class TVal> void RefHash2KeysTableOfEnumerator<TVal>::Reset()
{
    if(fLockPrimaryKey)
        fCurHash=fToEnum->fHash->getHashVal(fLockPrimaryKey, fToEnum->fHashModulus, fMemoryManager);
    else
        fCurHash = (unsigned int)-1;
    fCurElem = 0;
    findNext();
}


template <class TVal> void RefHash2KeysTableOfEnumerator<TVal>::setPrimaryKey(const void* key)
{
    fLockPrimaryKey=key;
    Reset();
}

// ---------------------------------------------------------------------------
//  RefHash2KeysTableOfEnumerator: Private helper methods
// ---------------------------------------------------------------------------
template <class TVal> void RefHash2KeysTableOfEnumerator<TVal>::findNext()
{
    //  Code to execute if we have to return only values with the primary key
    if(fLockPrimaryKey)
    {
        if(!fCurElem)
            fCurElem = fToEnum->fBucketList[fCurHash];
        else
            fCurElem = fCurElem->fNext;
        while (fCurElem && !fToEnum->fHash->equals(fLockPrimaryKey, fCurElem->fKey1) )
            fCurElem = fCurElem->fNext;
        // if we didn't found it, make so hasMoreElements() returns false
        if(!fCurElem)
            fCurHash = fToEnum->fHashModulus;
        return;
    }
    //
    //  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