/*
* 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.commons.jxpath;
import java.net.URL;
import javax.xml.transform.Source;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMResult;
import org.apache.commons.jxpath.xml.DocumentContainer;
import org.w3c.dom.Document;
/**
* An XML document container reads and parses XML only when it is
* accessed. JXPath traverses Containers transparently -
* you use the same paths to access objects in containers as you
* do to access those objects directly. You can create
* XMLDocumentContainers for various XML documents that may or
* may not be accessed by XPaths. If they are, they will be automatically
* read, parsed and traversed. If they are not - they won't be
* read at all.
*
* @deprecated 1.1 Please use {@link DocumentContainer}
*
* @author Dmitri Plotnikov
* @version $Revision: 652845 $ $Date: 2008-05-02 12:46:46 -0500 (Fri, 02 May 2008) $
*/
public class XMLDocumentContainer implements Container {
private DocumentContainer delegate;
private Object document;
private URL xmlURL;
private Source source;
/**
* Create a new XMLDocumentContainer.
* @param xmlURL a URL for an XML file. Use getClass().getResource(resourceName)
* to load XML from a resource file.
*/
public XMLDocumentContainer(URL xmlURL) {
this.xmlURL = xmlURL;
delegate = new DocumentContainer(xmlURL);
}
/**
* Create a new XMLDocumentContainer.
* @param source XML source
*/
public XMLDocumentContainer(Source source) {
this.source = source;
if (source == null) {
throw new RuntimeException("Source is null");
}
}
/**
* Reads XML, caches it internally and returns the Document.
* @return Object value
*/
public Object getValue() {
if (document == null) {
try {
if (source != null) {
DOMResult result = new DOMResult();
Transformer trans =
TransformerFactory.newInstance().newTransformer();
trans.transform(source, result);
document = (Document) result.getNode();
}
else {
document = delegate.getValue();
}
}
catch (Exception ex) {
throw new JXPathException(
"Cannot read XML from: "
+ (xmlURL != null
? xmlURL.toString()
: (source != null
? source.getSystemId()
: "<<undefined source>>")),
ex);
}
}
return document;
}
/**
* Throws an UnsupportedOperationException
* @param value to set
*/
public void setValue(Object value) {
throw new UnsupportedOperationException();
}
}
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