/*
* eXist Open Source Native XML Database
* Copyright (C) 2001-09 Wolfgang M. Meier
* wolfgang@exist-db.org
* 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.
*
* $Id$
*/
package org.exist.xquery.functions.util;
import org.apache.log4j.Logger;
import org.exist.dom.DocumentSet;
import org.exist.util.LockException;
import org.exist.xquery.Function;
import org.exist.xquery.FunctionSignature;
import org.exist.xquery.XPathException;
import org.exist.xquery.XQueryContext;
import org.exist.xquery.value.Item;
import org.exist.xquery.value.Sequence;
public abstract class LockFunction extends Function {
protected static final Logger logger = Logger.getLogger(LockFunction.class);
protected final boolean exclusive;
protected LockFunction(XQueryContext context, FunctionSignature signature, boolean exclusive) {
super(context, signature);
this.exclusive = exclusive;
}
/* (non-Javadoc)
* @see org.exist.xquery.Function#eval(org.exist.xquery.value.Sequence, org.exist.xquery.value.Item)
*/
public Sequence eval(Sequence contextSequence, Item contextItem)
throws XPathException {
final Sequence docsArg = getArgument(0).eval(contextSequence, contextItem);
final DocumentSet docs = docsArg.getDocumentSet();
try {
docs.lock(context.getBroker(), exclusive, false);
return getArgument(1).eval(contextSequence, contextItem);
} catch (final LockException e) {
throw new XPathException(this, "Could not lock document set", e);
} finally {
docs.unlock(exclusive);
}
}
/* (non-Javadoc)
* @see org.exist.xquery.Function#getCardinality()
*/
public int getCardinality() {
return getArgument(1).getCardinality();
}
/* (non-Javadoc)
* @see org.exist.xquery.Function#returnsType()
*/
public int returnsType() {
return getArgument(1).returnsType();
}
}