/*
* eXist Open Source Native XML Database
* Copyright (C) 2001-07 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.versioning.xquery;
import org.exist.dom.DocumentImpl;
import org.exist.dom.NodeProxy;
import org.exist.dom.QName;
import org.exist.memtree.DocumentBuilderReceiver;
import org.exist.memtree.InMemoryXMLStreamReader;
import org.exist.memtree.MemTreeBuilder;
import org.exist.memtree.NodeImpl;
import org.exist.numbering.NodeId;
import org.exist.stax.ExtendedXMLStreamReader;
import org.exist.versioning.DiffException;
import org.exist.versioning.Patch;
import org.exist.xquery.BasicFunction;
import org.exist.xquery.Cardinality;
import org.exist.xquery.FunctionSignature;
import org.exist.xquery.XPathException;
import org.exist.xquery.XQueryContext;
import org.exist.xquery.value.NodeValue;
import org.exist.xquery.value.Sequence;
import org.exist.xquery.value.SequenceType;
import org.exist.xquery.value.Type;
import javax.xml.stream.XMLStreamException;
import java.io.IOException;
public class PatchFunction extends BasicFunction {
public final static FunctionSignature signatures[] = {
new FunctionSignature(
new QName( "patch", VersioningModule.NAMESPACE_URI, VersioningModule.PREFIX ),
"Apply a patch to a document. The patch will be applied to the document of the node " +
"passed in first parameter. The second parameter should contain a version document as generated " +
"by eXist's VersioningTrigger. Note: though an arbitrary node can be passed in $a, the patch will " +
"always be applied to the entire document to which this node belongs.",
new SequenceType[] {
new SequenceType(Type.NODE, Cardinality.EXACTLY_ONE),
new SequenceType(Type.NODE, Cardinality.ZERO_OR_ONE)
},
new SequenceType( Type.ITEM, Cardinality.EXACTLY_ONE )
),
new FunctionSignature(
new QName( "annotate", VersioningModule.NAMESPACE_URI, VersioningModule.PREFIX ),
"Apply a patch to a document. The patch will be applied to the document of the node " +
"passed in first parameter. The second parameter should contain a version document as generated " +
"by eXist's VersioningTrigger. Note: though an arbitrary node can be passed in $a, the patch will " +
"always be applied to the entire document to which this node belongs.",
new SequenceType[] {
new SequenceType(Type.NODE, Cardinality.EXACTLY_ONE),
new SequenceType(Type.NODE, Cardinality.ZERO_OR_ONE)
},
new SequenceType( Type.ITEM, Cardinality.EXACTLY_ONE )
)
};
public PatchFunction(XQueryContext context, FunctionSignature signature) {
super(context, signature);
}
public Sequence eval(Sequence[] args, Sequence contextSequence) throws XPathException {
context.pushDocumentContext();
try {
ExtendedXMLStreamReader reader;
NodeValue nv = (NodeValue) args[0].itemAt(0);
if (nv.getImplementationType() == NodeValue.IN_MEMORY_NODE) {
NodeImpl node = (NodeImpl) nv;
reader = new InMemoryXMLStreamReader(node.getDocument(), node.getDocument());
} else {
NodeProxy proxy = (NodeProxy) nv;
reader = context.getBroker().newXMLStreamReader(new NodeProxy(proxy.getDocument(), NodeId.DOCUMENT_NODE, proxy.getDocument().getFirstChildAddress()), false);
}
nv = (NodeValue) args[1].itemAt(0);
if (nv.getImplementationType() == NodeValue.IN_MEMORY_NODE)
throw new XPathException("patch cannot be applied to in-memory documents");
NodeProxy diffProxy = (NodeProxy) nv;
DocumentImpl diff = diffProxy.getDocument();
MemTreeBuilder builder = context.getDocumentBuilder();
DocumentBuilderReceiver receiver = new DocumentBuilderReceiver(builder);
Patch patch = new Patch(context.getBroker(), diff);
if (isCalledAs("annotate"))
patch.annotate(reader, receiver);
else
patch.patch(reader, receiver);
NodeValue result = (NodeValue) builder.getDocument().getDocumentElement();
return result == null ? Sequence.EMPTY_SEQUENCE : result;
} catch (IOException e) {
throw new XPathException(this, e.getMessage(), e);
} catch (XMLStreamException e) {
throw new XPathException(this, e.getMessage(), e);
} catch (DiffException e) {
throw new XPathException(this, e.getMessage(), e);
} finally {
context.popDocumentContext();
}
}
}