/*
 * 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 "XalanDOMStringPool.hpp"


XALAN_CPP_NAMESPACE_BEGIN


const XalanDOMString	XalanDOMStringPool::s_emptyString;


XalanDOMStringPool::XalanDOMStringPool(
			block_size_type		theBlockSize,
			bucket_count_type	theBucketCount,
			bucket_size_type	theBucketSize) :
	m_stringAllocator(theBlockSize),
	m_stringCount(0),
	m_hashTable(theBucketCount, theBucketSize)
{
}


XalanDOMStringPool::~XalanDOMStringPool()
{
}


void
XalanDOMStringPool::clear()
{
	m_stringAllocator.reset();

	m_hashTable.clear();

	m_stringCount = 0;
}


size_t
XalanDOMStringPool::size() const
{
	assert(m_stringCount == m_hashTable.size());

	return m_stringCount;
}


const XalanDOMString&
XalanDOMStringPool::get(const XalanDOMString&	theString)
{
	return get(toCharArray(theString), length(theString));
}


const XalanDOMString&
XalanDOMStringPool::get(
			const XalanDOMChar*			theString,
			XalanDOMString::size_type	theLength)
{
	assert(m_stringCount == m_hashTable.size());

	if (theString == 0 || *theString == 0)
	{
		return s_emptyString;
	}
	else
	{
		const XalanDOMString::size_type		theActualLength = theLength == XalanDOMString::npos ? length(theString) : theLength;

		size_t	theBucketIndex;

		const XalanDOMString*	theTableString = m_hashTable.find(theString, theActualLength, &theBucketIndex);

		if (theTableString != 0)
		{
			return *theTableString;
		}
		else
		{
			// Not found, so insert the string...
			XalanDOMString* const	theNewString =
				m_stringAllocator.create(theString, theActualLength);
			assert(theNewString != 0);

			assert(theActualLength == length(*theNewString));

			++m_stringCount;

			// Insert the string into the hash table...
			m_hashTable.insert(*theNewString, theBucketIndex);

			assert(m_stringCount == m_hashTable.size());

			return *theNewString;
		}
	}
}


XALAN_CPP_NAMESPACE_END