/*
* The Apache Software License, Version 1.1
*
*
* Copyright (c) 2002 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Xalan" and "Apache Software Foundation" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache",
* nor may "Apache" appear in their name, without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation and was
* originally based on software copyright (c) 1999, Lotus
* Development Corporation., http://www.lotus.com. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*/
// This file uses 4 space indents, no tabs.
import java.io.FileInputStream;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.apache.xpath.domapi.XPathEvaluatorImpl;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.xpath.XPathEvaluator;
import org.w3c.dom.xpath.XPathNSResolver;
import org.w3c.dom.xpath.XPathResult;
import org.xml.sax.InputSource;
/**
* Very basic utility for applying the DOM L3 XPath API (currently in Last Call)
* to an xml file and printing information about the execution of the XPath object
* and the nodes it finds.
* Takes 2 arguments:
* (1) an xml filename
* (2) an XPath expression to apply to the file
* Examples:
* java ApplyXPathDOM foo.xml /
* java ApplyXPathDOM foo.xml /doc/name[1]/@last
*
*<p>See also the <a href='http://www.w3.org/TR/2002/WD-DOM-Level-3-XPath-20020328'>Document Object Model (DOM) Level 3 XPath Specification</a>.</p>
* @see XPathEvaluator
*
*/
public class ApplyXPathDOM
{
protected String filename = null;
protected String xpath = null;
/** Process input args and execute the XPath. */
public void doMain(String[] args)
throws Exception
{
filename = args[0];
xpath = args[1];
if ((filename != null) && (filename.length() > 0)
&& (xpath != null) && (xpath.length() > 0))
{
// Tell that we're loading classes and parsing, so the time it
// takes to do this doesn't get confused with the time to do
// the actual query and serialization.
System.out.println("Loading classes, parsing "+filename+", and setting up serializer");
// Set up a DOM tree to query.
InputSource in = new InputSource(new FileInputStream(filename));
DocumentBuilderFactory dfactory = DocumentBuilderFactory.newInstance();
dfactory.setNamespaceAware(true);
Document doc = dfactory.newDocumentBuilder().parse(in);
// Set up an identity transformer to use as serializer.
Transformer serializer = TransformerFactory.newInstance().newTransformer();
serializer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
// Use the DOM L3 XPath API to apply the xpath expression to the doc.
System.out.println("Querying DOM using "+xpath);
// Create an XPath evaluator and pass in the document.
XPathEvaluator evaluator = new XPathEvaluatorImpl(doc);
XPathNSResolver resolver = evaluator.createNSResolver(doc);
// Evaluate the xpath expression
XPathResult result = (XPathResult)evaluator.evaluate(xpath, doc, resolver, XPathResult.UNORDERED_NODE_ITERATOR_TYPE, null);
// Serialize the found nodes to System.out.
System.out.println("<output>");
Node n;
while ((n = result.iterateNext())!= null)
{
if (isTextNode(n)) {
// DOM may have more than one node corresponding to a
// single XPath text node. Coalesce all contiguous text nodes
// at this level
StringBuffer sb = new StringBuffer(n.getNodeValue());
for (
Node nn = n.getNextSibling();
isTextNode(nn);
nn = nn.getNextSibling()
) {
sb.append(nn.getNodeValue());
}
System.out.print(sb);
}
else {
serializer.transform(new DOMSource(n), new StreamResult(System.out));
}
System.out.println();
}
System.out.println("</output>");
}
else
{
System.out.println("Bad input args: " + filename + ", " + xpath);
}
}
/** Decide if the node is text, and so must be handled specially */
static boolean isTextNode(Node n) {
if (n == null)
return false;
short nodeType = n.getNodeType();
return nodeType == Node.CDATA_SECTION_NODE || nodeType == Node.TEXT_NODE;
}
/** Main method to run from the command line. */
public static void main (String[] args)
throws Exception
{
if (args.length != 2)
{
System.out.println("java ApplyXPathDOM filename.xml xpath\n"
+ "Reads filename.xml and applies the xpath; prints the nodelist found.");
return;
}
ApplyXPathDOM app = new ApplyXPathDOM();
app.doMain(args);
}
} // end of class ApplyXPathDOM