alvinalexander.com | career | drupal | java | mac | mysql | perl | scala | uml | unix  

What this is

This file is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Other links

The source code

/*
 * Copyright 1999-2004 The Apache Software Foundation
 *
 * Licensed 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 org.apache.commons.jxpath.xml.DocumentContainer
 *
 * @author Dmitri Plotnikov
 * @version $Revision: 1.11 $ $Date: 2004/02/29 14:17:42 $
 */
public class XMLDocumentContainer implements Container {

    private DocumentContainer delegate;
    private Object document;
    private URL xmlURL;
    private Source source;
    private String parser;

    /**
     * @param  URL is a URL for an XML file. Use getClass().getResource
     * (resourceName) to load XML from a resource file.
     */
    public XMLDocumentContainer(URL xmlURL) {
        delegate = new DocumentContainer(xmlURL);
    }

    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.
     */
    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()
                                : "<>")),
                    ex);
            }
        }
        return document;
    }

    /**
     * Throws an UnsupportedOperationException
     */
    public void setValue(Object value) {
        throw new UnsupportedOperationException();
    }
}
... this post is sponsored by my books ...

#1 New Release!

FP Best Seller

 

new blog posts

 

Copyright 1998-2024 Alvin Alexander, alvinalexander.com
All Rights Reserved.

A percentage of advertising revenue from
pages under the /java/jwarehouse URI on this website is
paid back to open source projects.