/*
* eXist Open Source Native XML Database
* Copyright (C) 2001-04 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.
*
* $Id$
*/
package org.exist.xquery.update;
import org.exist.EXistException;
import org.exist.dom.AttrImpl;
import org.exist.dom.DocumentImpl;
import org.exist.dom.ElementImpl;
import org.exist.dom.StoredNode;
import org.exist.dom.TextImpl;
import org.exist.security.Permission;
import org.exist.security.PermissionDeniedException;
import org.exist.storage.NotificationService;
import org.exist.storage.UpdateListener;
import org.exist.storage.txn.Txn;
import org.exist.util.LockException;
import org.exist.xquery.Dependency;
import org.exist.xquery.Expression;
import org.exist.xquery.Profiler;
import org.exist.xquery.XPathException;
import org.exist.xquery.XPathUtil;
import org.exist.xquery.XQueryContext;
import org.exist.xquery.util.Error;
import org.exist.xquery.util.ExpressionDumper;
import org.exist.xquery.util.Messages;
import org.exist.xquery.value.Item;
import org.exist.xquery.value.NodeValue;
import org.exist.xquery.value.Sequence;
import org.exist.xquery.value.StringValue;
import org.exist.xquery.value.Type;
import org.exist.xquery.value.ValueSequence;
import org.w3c.dom.Node;
/**
* @author wolf
*
*/
public class Replace extends Modification {
public Replace(XQueryContext context) {
super(context);
}
/**
* @param context
*/
public Replace(XQueryContext context, Expression select, Expression value) {
super(context, select, value);
}
/* (non-Javadoc)
* @see org.exist.xquery.AbstractExpression#eval(org.exist.xquery.value.Sequence, org.exist.xquery.value.Item)
*/
public Sequence eval(Sequence contextSequence, Item contextItem) 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);
if (contextItem != null)
context.getProfiler().message(this, Profiler.START_SEQUENCES, "CONTEXT ITEM", contextItem.toSequence());
}
if (contextItem != null)
contextSequence = contextItem.toSequence();
Sequence inSeq = select.eval(contextSequence);
if (inSeq.isEmpty())
return Sequence.EMPTY_SEQUENCE;
Sequence contentSeq = value.eval(contextSequence);
if (contentSeq.isEmpty())
throw new XPathException(this, Messages.getMessage(Error.UPDATE_EMPTY_CONTENT));
update(inSeq, contentSeq);
if (context.getProfiler().isEnabled())
context.getProfiler().end(this, "", Sequence.EMPTY_SEQUENCE);
return Sequence.EMPTY_SEQUENCE;
}
public void update(Sequence inSeq, Sequence contentSeq)
throws XPathException {
//START trap Replace failure
/* If we try and Replace a node at an invalid location,
* trap the error in a context variable,
* this is then accessible from xquery via. the context extension module - deliriumsky
* TODO: This trapping could be expanded further - basically where XPathException is thrown from thiss class
* TODO: Maybe we could provide more detailed messages in the trap, e.g. couldnt replace node `xyz` into `abc` becuase... this would be nicer for the end user of the xquery application
*/
if (!Type.subTypeOf(inSeq.getItemType(), Type.NODE))
{
//Indicate the failure to perform this update by adding it to the sequence in the context variable XQueryContext.XQUERY_CONTEXTVAR_XQUERY_UPDATE_ERROR
ValueSequence prevUpdateErrors = null;
XPathException xpe = new XPathException(this, Messages.getMessage(Error.UPDATE_SELECT_TYPE));
Object ctxVarObj = context.getXQueryContextVar(XQueryContext.XQUERY_CONTEXTVAR_XQUERY_UPDATE_ERROR);
if(ctxVarObj == null)
{
prevUpdateErrors = new ValueSequence();
}
else
{
prevUpdateErrors = (ValueSequence)XPathUtil.javaObjectToXPath(ctxVarObj, context);
}
prevUpdateErrors.add(new StringValue(xpe.getMessage()));
context.setXQueryContextVar(XQueryContext.XQUERY_CONTEXTVAR_XQUERY_UPDATE_ERROR, prevUpdateErrors);
if(!inSeq.isEmpty())
throw xpe; //TODO: should we trap this instead of throwing an exception - deliriumsky?
}
//END trap Replace failure
context.pushInScopeNamespaces();
contentSeq = deepCopy(contentSeq);
//start a transaction
Txn transaction = getTransaction();
try {
StoredNode ql[] = selectAndLock(transaction, inSeq);
IndexListener listener = new IndexListener(ql);
NotificationService notifier = context.getBroker().getBrokerPool().getNotificationService();
Item temp;
TextImpl text;
AttrImpl attribute;
ElementImpl parent;
for (int i = 0; i < ql.length; i++) {
StoredNode node = ql[i];
DocumentImpl doc = (DocumentImpl)node.getOwnerDocument();
if (!doc.getPermissions().validate(context.getUser(),
Permission.UPDATE))
throw new PermissionDeniedException(
"permission to update document denied");
doc.getMetadata().setIndexListener(listener);
//update the document
parent = (ElementImpl) node.getParentStoredNode();
if (parent == null)
throw new XPathException(this, "The root element of a document can not be replaced with 'update replace'. " +
"Please consider removing the document or use 'update value' to just replace the children of the root.");
switch (node.getNodeType()) {
case Node.ELEMENT_NODE:
temp = contentSeq.itemAt(0);
if (!Type.subTypeOf(temp.getType(), Type.NODE))
throw new XPathException(this,
Messages.getMessage(Error.UPDATE_REPLACE_ELEM_TYPE,
Type.getTypeName(temp.getType())));
parent.replaceChild(transaction, ((NodeValue)temp).getNode(), node);
break;
case Node.TEXT_NODE:
text = new TextImpl(contentSeq.getStringValue());
text.setOwnerDocument(doc);
parent.updateChild(transaction, node, text);
break;
case Node.ATTRIBUTE_NODE:
AttrImpl attr = (AttrImpl) node;
attribute = new AttrImpl(attr.getQName(), contentSeq.getStringValue());
attribute.setOwnerDocument(doc);
parent.updateChild(transaction, node, attribute);
break;
default:
throw new EXistException("unsupported node-type");
}
doc.getMetadata().clearIndexListener();
doc.getMetadata().setLastModified(System.currentTimeMillis());
modifiedDocuments.add(doc);
context.getBroker().storeXMLResource(transaction, doc);
notifier.notifyUpdate(doc, UpdateListener.UPDATE);
}
finishTriggers(transaction);
//commit the transaction
commitTransaction(transaction);
} catch (LockException e) {
throw new XPathException(this, e.getMessage(), e);
} catch (PermissionDeniedException e) {
throw new XPathException(this, e.getMessage(), e);
} catch (EXistException e) {
throw new XPathException(this, e.getMessage(), e);
} finally {
unlockDocuments();
context.popInScopeNamespaces();
}
}
/* (non-Javadoc)
* @see org.exist.xquery.Expression#dump(org.exist.xquery.util.ExpressionDumper)
*/
public void dump(ExpressionDumper dumper) {
dumper.display("update replace").nl();
dumper.startIndent();
select.dump(dumper);
dumper.nl().endIndent().display("with").nl().startIndent();
value.dump(dumper);
dumper.nl().endIndent();
}
public String toString() {
StringBuilder result = new StringBuilder();
result.append("update replace ");
result.append(select.toString());
result.append(" with ");
result.append(value.toString());
return result.toString();
}
}