/*
* eXist Open Source Native XML Database
* Copyright (C) 2001-2010 The eXist Project
* http://exist-db.org
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* $Id$
*/
package org.exist.validation;
import org.apache.log4j.Logger;
import org.apache.xerces.util.XMLGrammarPoolImpl;
import org.apache.xerces.xni.grammars.Grammar;
import org.apache.xerces.xni.grammars.XMLGrammarDescription;
import org.apache.xerces.xni.grammars.XMLGrammarPool;
import org.exist.Namespaces;
/**
* Wrapper around the Xerces XMLGrammarPoolImpl, so debugging of
* actions can be monitored. Javadoc copied from xml.apache.org.
*
* @author Dannes Wessels (dizzzz@exist-db.org)
*
* @see org.apache.xerces.xni.grammars.XMLGrammarPool
* @see org.apache.xerces.util.XMLGrammarPoolImpl
* @see org.apache.xerces.xni.grammars.Grammar
* @see org.apache.xerces.xni.grammars.XMLGrammarDescription
*/
public class GrammarPool implements XMLGrammarPool {
private final static Logger logger = Logger.getLogger(GrammarPool.class);
private XMLGrammarPool pool;
/**
* Constructs a grammar pool with a default number of buckets.
*/
public GrammarPool() {
if (logger.isInfoEnabled())
{logger.info("Initializing GrammarPool.");}
pool = new XMLGrammarPoolImpl();
}
/**
* Constructs a grammar pool with a default number of buckets using pool.
*
* @param pool The supplied grammar pool is reused.
*/
public GrammarPool(XMLGrammarPool pool) {
if (logger.isInfoEnabled())
{logger.info("Initializing GrammarPool using supplied pool.");}
this.pool=pool;
}
/**
* Retrieve the initial known set of grammars. this method is called
* by a validator before the validation starts. the application can provide
* an initial set of grammars available to the current validation attempt.
*
* @see org.apache.xerces.xni.grammars.XMLGrammarPool#retrieveInitialGrammarSet(String)
*
* @param type The type of the grammar, from the
* org.apache.xerces.xni.grammars.Grammar interface.
* @return The set of grammars the validator may put in its "bucket"
*/
public Grammar[] retrieveInitialGrammarSet(String type) {
if (logger.isDebugEnabled())
{logger.debug("Retrieve initial grammarset ("+type+").");}
final Grammar[] grammars = pool.retrieveInitialGrammarSet(type);
if (logger.isDebugEnabled())
{logger.debug("Found "+grammars.length+" grammars.");}
return grammars;
}
/**
* Return the final set of grammars that the validator ended up with.
*
* @see org.apache.xerces.xni.grammars.XMLGrammarPool#cacheGrammars(String,Grammar[])
*
* @param type The type of the grammars being returned
* @param grammar an array containing the set of grammars being
* returned; order is not significant.
*/
public void cacheGrammars(String type, Grammar[] grammar) {
if (logger.isDebugEnabled())
{logger.debug("Cache "+grammar.length+" grammars ("+type + ").");}
pool.cacheGrammars(type, grammar);
}
/**
* Allows the XMLGrammarPool to store grammars when its
* cacheGrammars(String, Grammar[]) method is called. This is the default
* state of the object.
*
* @see org.apache.xerces.xni.grammars.XMLGrammarPool#unlockPool
*/
public void unlockPool() {
if (logger.isDebugEnabled())
{logger.debug("Unlock grammarpool.");}
pool.unlockPool();
}
/**
* This method requests that the application retrieve a grammar
* corresponding to the given GrammarIdentifier from its cache. If it
* cannot do so it must return null; the parser will then call the
* EntityResolver. An application must not call its EntityResolver itself
* from this method; this may result in infinite recursions.
*
* @see org.apache.xerces.xni.grammars.XMLGrammarPool#retrieveGrammar(XMLGrammarDescription)
*
* @param xgd The description of the Grammar being requested.
* @return the Grammar corresponding to this description or null
* if no such Grammar is known.
*/
public Grammar retrieveGrammar(XMLGrammarDescription xgd) {
if(xgd==null){
if (logger.isDebugEnabled())
{logger.debug("XMLGrammarDescription is null");}
return null;
}
if(xgd.getNamespace()!=null){
if (logger.isDebugEnabled())
{logger.debug("Retrieve grammar for namespace '"+xgd.getNamespace()+"'.");}
}
if(xgd.getPublicId()!=null){
if (logger.isDebugEnabled())
{logger.debug("Retrieve grammar for publicId '"+xgd.getPublicId()+"'.");}
}
return pool.retrieveGrammar(xgd);
}
/**
* Causes the XMLGrammarPool not to store any grammars when the
* cacheGrammars(String, Grammar[[]) method is called.
*
* @see org.apache.xerces.xni.grammars.XMLGrammarPool#lockPool
*/
public void lockPool() {
if (logger.isDebugEnabled())
{logger.debug("Lock grammarpool.");}
pool.lockPool();
}
/**
* Removes all grammars from the pool.
*
* @see org.apache.xerces.xni.grammars.XMLGrammarPool#clear
*/
public void clear() {
if (logger.isDebugEnabled())
{logger.debug("Clear grammarpool.");}
pool.clear();
}
/**
* Removes all DTD grammars from the pool. Workaround for Xerces bug.
*
* @see org.apache.xerces.xni.grammars.XMLGrammarPool#clear
*/
public void clearDTDs() {
//if (logger.isDebugEnabled())
// logger.debug("Removing DTD's from grammarpool.");
final Grammar dtds[] = retrieveInitialGrammarSet(Namespaces.DTD_NS);
if(dtds.length>0){
if (logger.isDebugEnabled())
{logger.debug("Removing "+dtds.length+" DTDs.");}
final Grammar schemas[] = retrieveInitialGrammarSet(Namespaces.SCHEMA_NS);
clear();
cacheGrammars(Namespaces.SCHEMA_NS, schemas);
} else {
//if (logger.isDebugEnabled())
// logger.debug("No DTDs to be removed.");
}
}
}