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	/*
	* Copyright (c) 2007, 2017, Oracle and/or its affiliates. All rights reserved.
	*/
	/*
	* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* this work for additional information regarding copyright ownership.
	* The ASF licenses this file to You 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.
	*/

	package com.sun.org.apache.xml.internal.utils;

	import com.sun.org.apache.xalan.internal.XalanConstants;
	import com.sun.org.apache.xalan.internal.utils.XMLSecurityManager;
	import java.util.HashMap;
	import javax.xml.XMLConstants;
	import javax.xml.catalog.CatalogFeatures;
	import jdk.xml.internal.JdkXmlFeatures;
	import jdk.xml.internal.JdkXmlUtils;
	import jdk.xml.internal.SecuritySupport;
	import org.xml.sax.SAXException;
	import org.xml.sax.SAXNotRecognizedException;
	import org.xml.sax.SAXNotSupportedException;
	import org.xml.sax.XMLReader;

	/**
	* Creates XMLReader objects and caches them for re-use.
	* This class follows the singleton pattern.
	*
	* @LastModified: Sep 2017
	*/
	public class XMLReaderManager {

	private static final XMLReaderManager m_singletonManager =
	new XMLReaderManager();
	private static final String property = "org.xml.sax.driver";

	/**
	* Cache of XMLReader objects
	*/
	private ThreadLocal<ReaderWrapper> m_readers;

	/**
	* Keeps track of whether an XMLReader object is in use.
	*/
	private HashMap<XMLReader, Boolean> m_inUse;

	private boolean m_overrideDefaultParser;

	private boolean _secureProcessing;
	/**
	* protocols allowed for external DTD references in source file and/or stylesheet.
	*/
	private String _accessExternalDTD = XalanConstants.EXTERNAL_ACCESS_DEFAULT;

	private XMLSecurityManager _xmlSecurityManager;

	//Catalog Feature
	private boolean _useCatalog;
	private CatalogFeatures _catalogFeatures;

	private int _cdataChunkSize;

	/**
	* Hidden constructor
	*/
	private XMLReaderManager() {
	}

	/**
	* Retrieves the singleton reader manager
	*/
	public static XMLReaderManager getInstance(boolean overrideDefaultParser) {
	m_singletonManager.setOverrideDefaultParser(overrideDefaultParser);
	return m_singletonManager;
	}

	/**
	* Retrieves a cached XMLReader for this thread, or creates a new
	* XMLReader, if the existing reader is in use. When the caller no
	* longer needs the reader, it must release it with a call to
	* {@link #releaseXMLReader}.
	*/
	public synchronized XMLReader getXMLReader() throws SAXException {
	XMLReader reader;

	if (m_readers == null) {
	// When the m_readers.get() method is called for the first time
	// on a thread, a new XMLReader will automatically be created.
	m_readers = new ThreadLocal<>();
	}

	if (m_inUse == null) {
	m_inUse = new HashMap<>();
	}

	/**
	* Constructs a new XMLReader if:
	* (1) the cached reader for this thread is in use, or
	* (2) the requirement for overriding has changed,
	* (3) the cached reader isn't an instance of the class set in the
	* 'org.xml.sax.driver' property
	*
	* otherwise, returns the cached reader
	*/
	ReaderWrapper rw = m_readers.get();
	boolean threadHasReader = (rw != null);
	reader = threadHasReader ? rw.reader : null;
	String factory = SecuritySupport.getSystemProperty(property);
	if (threadHasReader && m_inUse.get(reader) != Boolean.TRUE &&
	(rw.overrideDefaultParser == m_overrideDefaultParser) &&
	( factory == null \|\| reader.getClass().getName().equals(factory))) {
	m_inUse.put(reader, Boolean.TRUE);
	} else {
	reader = JdkXmlUtils.getXMLReader(m_overrideDefaultParser, _secureProcessing);

	// Cache the XMLReader if this is the first time we've created
	// a reader for this thread.
	if (!threadHasReader) {
	m_readers.set(new ReaderWrapper(reader, m_overrideDefaultParser));
	m_inUse.put(reader, Boolean.TRUE);
	}
	}

	//reader is cached, but this property might have been reset
	JdkXmlUtils.setXMLReaderPropertyIfSupport(reader, XMLConstants.ACCESS_EXTERNAL_DTD,
	_accessExternalDTD, true);

	JdkXmlUtils.setXMLReaderPropertyIfSupport(reader, JdkXmlUtils.CDATA_CHUNK_SIZE,
	_cdataChunkSize, false);

	String lastProperty = "";
	try {
	if (_xmlSecurityManager != null) {
	for (XMLSecurityManager.Limit limit : XMLSecurityManager.Limit.values()) {
	lastProperty = limit.apiProperty();
	reader.setProperty(lastProperty,
	_xmlSecurityManager.getLimitValueAsString(limit));
	}
	if (_xmlSecurityManager.printEntityCountInfo()) {
	lastProperty = XalanConstants.JDK_ENTITY_COUNT_INFO;
	reader.setProperty(XalanConstants.JDK_ENTITY_COUNT_INFO, XalanConstants.JDK_YES);
	}
	}
	} catch (SAXException se) {
	XMLSecurityManager.printWarning(reader.getClass().getName(), lastProperty, se);
	}

	boolean supportCatalog = true;
	try {
	reader.setFeature(JdkXmlUtils.USE_CATALOG, _useCatalog);
	}
	catch (SAXNotRecognizedException \| SAXNotSupportedException e) {
	supportCatalog = false;
	}

	if (supportCatalog && _useCatalog && _catalogFeatures != null) {
	try {
	for (CatalogFeatures.Feature f : CatalogFeatures.Feature.values()) {
	reader.setProperty(f.getPropertyName(), _catalogFeatures.get(f));
	}
	} catch (SAXNotRecognizedException e) {
	//shall not happen for internal settings
	}
	}
	return reader;
	}

	/**
	* Mark the cached XMLReader as available. If the reader was not
	* actually in the cache, do nothing.
	*
	* @param reader The XMLReader that's being released.
	*/
	public synchronized void releaseXMLReader(XMLReader reader) {
	// If the reader that's being released is the cached reader
	// for this thread, remove it from the m_isUse list.
	ReaderWrapper rw = m_readers.get();
	if (rw.reader == reader && reader != null) {
	m_inUse.remove(reader);
	}
	}
	/**
	* Return the state of the services mechanism feature.
	*/
	public boolean overrideDefaultParser() {
	return m_overrideDefaultParser;
	}

	/**
	* Set the state of the services mechanism feature.
	*/
	public void setOverrideDefaultParser(boolean flag) {
	m_overrideDefaultParser = flag;
	}

	/**
	* Set feature
	*/
	public void setFeature(String name, boolean value) {
	if (name.equals(XMLConstants.FEATURE_SECURE_PROCESSING)) {
	_secureProcessing = value;
	} else if (XMLConstants.USE_CATALOG.equals(name)) {
	_useCatalog = value;
	}
	}

	/**
	* Get property value
	*/
	public Object getProperty(String name) {
	if (name.equals(XMLConstants.ACCESS_EXTERNAL_DTD)) {
	return _accessExternalDTD;
	} else if (name.equals(XalanConstants.SECURITY_MANAGER)) {
	return _xmlSecurityManager;
	}
	return null;
	}

	/**
	* Set property.
	*/
	public void setProperty(String name, Object value) {
	if (name.equals(XMLConstants.ACCESS_EXTERNAL_DTD)) {
	_accessExternalDTD = (String)value;
	} else if (name.equals(XalanConstants.SECURITY_MANAGER)) {
	_xmlSecurityManager = (XMLSecurityManager)value;
	} else if (JdkXmlFeatures.CATALOG_FEATURES.equals(name)) {
	_catalogFeatures = (CatalogFeatures)value;
	} else if (JdkXmlUtils.CDATA_CHUNK_SIZE.equals(name)) {
	_cdataChunkSize = JdkXmlUtils.getValue(value, _cdataChunkSize);
	}
	}

	class ReaderWrapper {
	XMLReader reader;
	boolean overrideDefaultParser;

	public ReaderWrapper(XMLReader reader, boolean overrideDefaultParser) {
	this.reader = reader;
	this.overrideDefaultParser = overrideDefaultParser;
	}
	}
	}

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