DOMPrinter.java

/*******************************************************************************
 * $Id$
 * $Author$
 * $Date$
 *
 * Copyright 2002 - YAJUL Developers, Joshua Davis, Kent Vogel.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
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package org.yajul.xml;

import org.w3c.dom.Node;

import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.TransformerConfigurationException;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import java.io.OutputStream;
import java.io.Writer;
import java.io.ByteArrayOutputStream;

/**
 * Provides functions that print DOM objects to streams.  Works with
 * any JAXP1.1 compliant implementation (e.g. XALAN).
 * @author Joshua Davis
 */
public class DOMPrinter
{
    /** Transformer output property value for 'true'. **/
    public static final String TRUE = "yes";
    /** Transformer output property value for 'false'. **/
    public static final String FALSE = "no";

    /**
     * Prints a node (Document or Element) into a string, without the
     * XML declaration.
     * @param node The new (Document or Element) to print.
     * @throws TransformerException - If there was a problem.
     */
    public static final String nodeToString(Node node) throws TransformerException
    {
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        printNode(node,out);
        return out.toString();
    }

    /**
     * Prints a node (Document or Element) to the stream, without the
     * XML declaration.
     * @param node The new (Document or Element) to print.
     * @param stream The stream to print to.
     * @throws TransformerException - If there was a problem.
     */
    public static final void printNode(
            Node node,
            OutputStream stream) throws TransformerException
    {
        printNode(node, stream, true);
    }

    /**
     * Prints a node (Document or Element) to the stream, without the
     * XML declaration.
     * @param node The new (Document or Element) to print.
     * @param stream The stream to print to.
     * @param omitXMLDeclaration Use true to omit the
     * <code>>?xml version="1.0" ?<</code> declaration.
     * @throws TransformerException - If there was a problem.
     */
    public static final void printNode(
            Node node,
            OutputStream stream,
            boolean omitXMLDeclaration) throws TransformerException
    {
        // Create a default transformer.
        Transformer transformer = createTransformer(omitXMLDeclaration);

        // Do the transform.
        transformer.transform(new DOMSource(node), new StreamResult(stream));
    }

    /**
     * Prints a node (Document or Element) to the writer, without the
     * XML declaration.
     * @param node The new (Document or Element) to print.
     * @param writer The writer to print to.
     * @param omitXMLDeclaration Use true to omit the
     * <code>>?xml version="1.0" ?<</code> declaration.
     * @throws TransformerException - If there was a problem.
     */
    public static final void printNode(
            Node node,
            Writer writer,
            boolean omitXMLDeclaration) throws TransformerException
    {
        // Create a default transformer.
        Transformer transformer = createTransformer(omitXMLDeclaration);

        // Do the transform.
        transformer.transform(new DOMSource(node), new StreamResult(writer));
    }

    // -- Implementation methods --

    private static Transformer createTransformer(boolean omitXMLDeclaration)
            throws TransformerConfigurationException
    {
        TransformerFactory factory = TransformerFactory.newInstance();
        Transformer transformer = factory.newTransformer();

        // Set the output properties.
        setOutputProperties(transformer, omitXMLDeclaration);
        return transformer;
    }

    private static final void setOutputProperties(Transformer transformer,
                                                  boolean omitXMLDeclaration)
    {
        // Set the attributes of the transformer.
        transformer.setOutputProperty(OutputKeys.METHOD, "xml");
        transformer.setOutputProperty(OutputKeys.INDENT, TRUE);
        transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION,
                omitXMLDeclaration ? TRUE : FALSE);
    }
}