src/xalanc/PlatformSupport/XalanDOMStringHashTable.cpp

/*
 * Copyright 1999-2004 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.
 */

// Class header file...
#include "XalanDOMStringHashTable.hpp"



#include <algorithm>



#include "DOMStringHelper.hpp"



XALAN_CPP_NAMESPACE_BEGIN



XalanDOMStringHashTable::XalanDOMStringHashTable(
			size_t		theBucketCount,
			size_t		theBucketSize) :

	m_bucketCount(theBucketCount),
	m_bucketSize(theBucketSize),
	m_buckets(new BucketType[theBucketCount]),
	m_count(0),
	m_collisions(0)
{
}



void
XalanDOMStringHashTable::clear()
{
	for(size_t i = 0; i < m_bucketCount; ++i)
	{
		m_buckets[i].clear();
	}

#if !defined(NDEBUG)
	m_collisions = 0;
#endif
	m_count = 0;
}



void
XalanDOMStringHashTable::getBucketCounts(BucketCountsType&	theVector) const
{
	for(size_t i = 0; i < m_bucketCount; ++i)
	{
		const bucket_size_type	size = m_buckets[i].size();

		theVector.push_back(size);
	}
}



#if defined(XALAN_NEEDS_EXPLICIT_TEMPLATE_INSTANTIATION)
bool
XalanDOMStringHashTable::equalsXalanDOMString::operator()(const XalanDOMString*		theString) const
{
	if (m_length != length(*theString))
	{
		return false;
	}
	else
	{
		return equals(m_string, c_wstr(*theString), m_length);
	}
}
#else
struct
equalsXalanDOMString
{
	equalsXalanDOMString(
			const XalanDOMChar*			theString,
			XalanDOMString::size_type	theLength) :
		m_string(theString),
		m_length(theLength)
	{
	}

	bool
	operator()(const XalanDOMString*	theString) const
	{
		if (m_length != length(*theString))
		{
			return false;
		}
		else
		{
			return equals(m_string, c_wstr(*theString), m_length);
		}
	}

private:

	const XalanDOMChar* const			m_string;

	const XalanDOMString::size_type		m_length;
};
#endif



const XalanDOMString*
XalanDOMStringHashTable::find(
			const XalanDOMString&	theString,
			size_t*					theBucketIndex) const
{
	return find(c_wstr(theString), length(theString), theBucketIndex);
}



const XalanDOMString*
XalanDOMStringHashTable::find(
			const XalanDOMChar*			theString,
			XalanDOMString::size_type	theLength,
			size_t*						theBucketIndex) const
{
	assert(theString != 0);

	const XalanDOMString::size_type		theActualLength =
		theLength == XalanDOMString::npos ? length(theString) : theLength;

	const XalanDOMString::size_type		theHash = XalanDOMString::hash(theString, theActualLength);

	const size_t	theLocalBucketIndex = theHash % m_bucketCount;

	assert(theLocalBucketIndex < m_bucketCount);

	const BucketType&	theBucket = m_buckets[theLocalBucketIndex];

	if (theBucketIndex != 0)
	{
		*theBucketIndex = theLocalBucketIndex;
	}

	XALAN_USING_STD(find_if)

	const BucketType::const_iterator	i =
		find_if(
				theBucket.begin(),
				theBucket.end(),
				equalsXalanDOMString(theString, theActualLength));

	if (i == theBucket.end())
	{
		return 0;
	}
	else
	{
		return *i;
	}
}



void
XalanDOMStringHashTable::insert(const XalanDOMString&	theString)
{
	const XalanDOMString::size_type		theHash = theString.hash();

	const size_t	theBucketIndex = theHash % m_bucketCount;

	assert(theBucketIndex < m_bucketCount);

	BucketType&	theBucket = m_buckets[theBucketIndex];

#if !defined(NDEBUG)
	if (theBucket.empty() == false)
	{
		++m_collisions;
	}
#endif

	theBucket.reserve(m_bucketSize);

	theBucket.push_back(&theString);

	++m_count;
}



void
XalanDOMStringHashTable::insert(
			const XalanDOMString&	theString,
			size_t					theBucketIndex)
{
	assert(theBucketIndex == theString.hash() % m_bucketCount);
	assert(theBucketIndex < m_bucketCount);

	BucketType&		theBucket = m_buckets[theBucketIndex];

#if !defined(NDEBUG)
	if (theBucket.empty() == false)
	{
		++m_collisions;
	}
#endif

	theBucket.reserve(m_bucketSize);

	theBucket.push_back(&theString);

	++m_count;
}



XALAN_CPP_NAMESPACE_END