/*
* eXist Open Source Native XML Database
* Copyright (C) 2001-2012 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.xquery;
import org.exist.memtree.DocumentBuilderReceiver;
import org.exist.memtree.MemTreeBuilder;
import org.exist.memtree.TextImpl;
import org.exist.xquery.util.ExpressionDumper;
import org.exist.xquery.value.Item;
import org.exist.xquery.value.Sequence;
import org.exist.xquery.value.SequenceIterator;
import org.exist.xquery.value.Type;
import org.xml.sax.SAXException;
/**
* Represents an enclosed expression <code>{expr}</code> inside element
* content. Enclosed expressions within attribute values are processed by
* {@link org.exist.xquery.AttributeConstructor}.
*
* @author Wolfgang Meier <wolfgang@exist-db.org>
*/
public class EnclosedExpr extends PathExpr {
/**
*
*/
public EnclosedExpr(XQueryContext context) {
super(context);
}
public void analyze(AnalyzeContextInfo contextInfo) throws XPathException {
final AnalyzeContextInfo newContextInfo = new AnalyzeContextInfo(contextInfo);
newContextInfo.removeFlag(IN_NODE_CONSTRUCTOR);
super.analyze(newContextInfo);
}
/* (non-Javadoc)
* @see org.exist.xquery.AbstractExpression#eval(org.exist.xquery.StaticContext,
* org.exist.dom.DocumentSet, org.exist.xquery.value.Sequence)
*/
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();
}
// evaluate the expression
context.pushDocumentContext();
Sequence result;
try {
result = super.eval(contextSequence, null);
} finally {
context.popDocumentContext();
}
// create the output
final MemTreeBuilder builder = context.getDocumentBuilder();
final DocumentBuilderReceiver receiver = new DocumentBuilderReceiver(builder);
receiver.checkNS = true;
try {
final SequenceIterator i = result.iterate();
Item next = i.nextItem();
StringBuilder buf = null;
boolean allowAttribs = true;
while (next != null) {
context.proceed(this, builder);
// if item is an atomic value, collect the string values of all
// following atomic values and separate them by a space.
if (Type.subTypeOf(next.getType(), Type.ATOMIC)) {
if (buf == null)
{buf = new StringBuilder();}
else if (buf.length() > 0)
{buf.append(' ');}
buf.append(next.getStringValue());
allowAttribs = false;
next = i.nextItem();
//If the item is a node, flush any collected character data and
//copy the node to the target doc.
} else if (Type.subTypeOf(next.getType(), Type.NODE)) {
//It is possible for a text node constructor to construct a text node containing a zero-length string.
//However, if used in the content of a constructed element or document node,
//such a text node will be deleted or merged with another text node.
if (next instanceof TextImpl && ((TextImpl)next).getStringValue().isEmpty()) {
next = i.nextItem();
continue;
}
if (buf != null && buf.length() > 0) {
receiver.characters(buf);
buf.setLength(0);
}
if (next.getType() == Type.ATTRIBUTE && !allowAttribs)
{throw new XPathException(this, ErrorCodes.XQTY0024,
"An attribute may not appear after another child node.");}
next.copyTo(context.getBroker(), receiver);
allowAttribs = next.getType() == Type.ATTRIBUTE || next.getType() == Type.NAMESPACE;
next = i.nextItem();
}
}
// flush remaining character data
if (buf != null && buf.length() > 0)
{receiver.characters(buf);}
} catch (final SAXException e) {
LOG.warn("SAXException during serialization: " + e.getMessage(), e);
throw new XPathException(this, e);
}
if (context.getProfiler().isEnabled())
{context.getProfiler().end(this, "", result);}
return result;
}
/* (non-Javadoc)
* @see org.exist.xquery.PathExpr#dump(org.exist.xquery.util.ExpressionDumper)
*/
public void dump(ExpressionDumper dumper) {
dumper.display("{");
dumper.startIndent();
super.dump(dumper);
dumper.endIndent();
dumper.nl().display("}");
}
public String toString() {
final StringBuilder result = new StringBuilder();
result.append("{");
result.append(super.toString());
result.append("}");
return result.toString();
}
public void accept(ExpressionVisitor visitor) {
visitor.visitPathExpr(this);
}
@Override
public boolean allowMixedNodesInReturn() {
return true;
}
@Override
public Expression simplify() {
return this;
}
}