/*
* eXist Open Source Native XML Database
* Copyright (C) 2006-2009 The eXist Team
*
* 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 program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* $Id: QNameIndexLookup.java 3063 2006-04-05 20:49:44Z brihaye $
*/
package org.exist.xquery.functions.util;
import java.util.HashMap;
import java.util.Map;
import org.apache.log4j.Logger;
import org.exist.dom.DocumentSet;
import org.exist.dom.NodeSet;
import org.exist.dom.QName;
import org.exist.indexing.IndexWorker;
import org.exist.indexing.OrderedValuesIndex;
import org.exist.storage.Indexable;
import org.exist.util.Occurrences;
import org.exist.util.ValueOccurrences;
import org.exist.xquery.BasicFunction;
import org.exist.xquery.Cardinality;
import org.exist.xquery.Dependency;
import org.exist.xquery.FunctionSignature;
import org.exist.xquery.Profiler;
import org.exist.xquery.XPathException;
import org.exist.xquery.XQueryContext;
import org.exist.xquery.value.FunctionParameterSequenceType;
import org.exist.xquery.value.FunctionReturnSequenceType;
import org.exist.xquery.value.IntegerValue;
import org.exist.xquery.value.Sequence;
import org.exist.xquery.value.SequenceType;
import org.exist.xquery.value.Type;
/**
* @author Pierrick Brihaye <pierrick.brihaye@free.fr>
*/
public class IndexKeyDocuments extends BasicFunction {
protected static final Logger logger = Logger.getLogger(IndexKeyDocuments.class);
protected static final FunctionParameterSequenceType nodeParam = new FunctionParameterSequenceType("nodes", Type.NODE, Cardinality.ZERO_OR_MORE, "The nodes whose content is indexed");
protected static final FunctionParameterSequenceType valueParam = new FunctionParameterSequenceType("value", Type.ATOMIC, Cardinality.EXACTLY_ONE, "The indexed value to search for");
protected static final FunctionParameterSequenceType indexParam = new FunctionParameterSequenceType("index", Type.STRING, Cardinality.EXACTLY_ONE, "The index in which the search is made");
protected static final FunctionReturnSequenceType result = new FunctionReturnSequenceType(Type.INTEGER, Cardinality.ZERO_OR_ONE, "the number of documents for the indexed value");
public final static FunctionSignature[] signatures = {
new FunctionSignature(
new QName("index-key-documents", UtilModule.NAMESPACE_URI, UtilModule.PREFIX),
"Return the number of documents for an indexed value.",
new SequenceType[] { nodeParam, valueParam },
result),
new FunctionSignature(
new QName("index-key-documents", UtilModule.NAMESPACE_URI, UtilModule.PREFIX),
"Return the number of documents for an indexed value.",
new SequenceType[] { nodeParam, valueParam, indexParam },
result)
};
public IndexKeyDocuments(XQueryContext context, FunctionSignature signature) {
super(context, signature);
}
public Sequence eval(Sequence[] args, Sequence contextSequence) throws XPathException {
if (context.getProfiler().isEnabled()) {
context.getProfiler().start(this);
context.getProfiler().message(this, Profiler.DEPENDENCIES, "DEPENDENCIES", Dependency.getDependenciesName(this.getDependencies()));
if (contextSequence != null)
{context.getProfiler().message(this, Profiler.START_SEQUENCES, "CONTEXT SEQUENCE", contextSequence);}
}
Sequence result;
if (args[0].isEmpty())
{result = Sequence.EMPTY_SEQUENCE;}
else {
final NodeSet nodes = args[0].toNodeSet();
final DocumentSet docs = nodes.getDocumentSet();
if (this.getArgumentCount() == 3) {
final IndexWorker indexWorker = context.getBroker().getIndexController().getWorkerByIndexName(args[2].itemAt(0).getStringValue());
//Alternate design
//IndexWorker indexWorker = context.getBroker().getBrokerPool().getIndexManager().getIndexByName(args[2].itemAt(0).getStringValue()).getWorker();
if (indexWorker == null)
{throw new XPathException(this, "Unknown index: " + args[2].itemAt(0).getStringValue());}
final Map<String, Object> hints = new HashMap<String, Object>();
if (indexWorker instanceof OrderedValuesIndex)
{hints.put(OrderedValuesIndex.START_VALUE, args[1]);}
else
{logger.warn(indexWorker.getClass().getName() + " isn't an instance of org.exist.indexing.OrderedIndexWorker. Start value '" + args[1] + "' ignored." );}
final Occurrences[] occur = indexWorker.scanIndex(context, docs, nodes, hints);
if (occur.length == 0)
{result= Sequence.EMPTY_SEQUENCE;}
else
{result = new IntegerValue(occur[0].getDocuments());}
} else {
final ValueOccurrences occur[] = context.getBroker().getValueIndex()
.scanIndexKeys(docs, nodes, (Indexable) args[1]);
if (occur.length == 0)
{result= Sequence.EMPTY_SEQUENCE;}
else
{result = new IntegerValue(occur[0].getDocuments());}
}
}
if (context.getProfiler().isEnabled())
{context.getProfiler().end(this, "", result);}
return result;
}
}