/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.cocoon.pipeline.component.xpointer;
import java.io.IOException;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;
import org.apache.cocoon.pipeline.component.sax.SAXConsumer;
import org.apache.cocoon.pipeline.util.dom.DOMUtils;
import org.w3c.dom.Document;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.LocatorImpl;
public final class XPointerPart implements PointerPart {
private static final XPathFactory XPF = XPathFactory.newInstance();
private String expression;
public XPointerPart(String expression) {
this.expression = expression;
}
public boolean process(XPointerContext xpointerContext) throws SAXException, IOException {
Document document = xpointerContext.getDocument();
XPath xpath = XPF.newXPath();
xpath.setNamespaceContext(xpointerContext);
XPathExpression xpathExpression;
try {
xpathExpression = xpath.compile(expression);
} catch (XPathExpressionException e) {
throw new SAXException("XPointer: expression \"" + expression + "\" is not a valid XPath expression", e);
}
try {
NodeList nodeList = (NodeList) xpathExpression.evaluate(document, XPathConstants.NODESET);
if (nodeList.getLength() > 0) {
SAXConsumer consumer = xpointerContext.getXmlConsumer();
LocatorImpl locator = new LocatorImpl();
locator.setSystemId(xpointerContext.getSource().toString());
consumer.setDocumentLocator(locator);
for (int i = 0; i < nodeList.getLength(); i++) {
DOMUtils.stream(nodeList.item(i), consumer);
}
return true;
} else {
if (xpointerContext.getLogger().isDebugEnabled()) {
xpointerContext.getLogger().debug("XPointer: expression \"" + expression + "\" gave no results.");
}
return false;
}
} catch (XPathExpressionException e) {
throw new SAXException("XPointer: impossible to select DOM fragment using expression \"" + expression
+ "\", see nested exception", e);
}
}
}