Ant example source code file (EchoXML.java)

This example Ant source code file (EchoXML.java) 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.

Java - Ant tags/keywords

buildexception, buildexception, dom, domelementwriter, domelementwriter, echoxml, error_no_xml, file, file, io, no, no, node, string, xml, xmlfragment

The EchoXML.java source code

/*
 *  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.tools.ant.taskdefs;

import java.io.File;
import java.io.OutputStream;
import java.io.FileOutputStream;

import org.apache.tools.ant.Project;
import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.util.XMLFragment;
import org.apache.tools.ant.util.DOMElementWriter;
import org.apache.tools.ant.util.FileUtils;

import org.w3c.dom.Node;
import org.w3c.dom.Element;

/**
 * Echo XML.
 *
 * Known limitations:
 * <ol>
 * <li>Currently no XMLNS support
 * <li>Processing Instructions get ignored
 * <li>Encoding is always UTF-8
 * </ol>
 *
 * @since Ant 1.7
 */
public class EchoXML extends XMLFragment {

    private File file;
    private boolean append;
    private static final String ERROR_NO_XML = "No nested XML specified";

    /**
     * Set the output file.
     * @param f the output file.
     */
    public void setFile(File f) {
        file = f;
    }

    /**
     * Set whether to append the output file.
     * @param b boolean append flag.
     */
    public void setAppend(boolean b) {
        append = b;
    }

    /**
     * Execute the task.
     */
    public void execute() {
        DOMElementWriter writer = new DOMElementWriter(!append);
        OutputStream os = null;
        try {
            if (file != null) {
                os = new FileOutputStream(file.getAbsolutePath(), append);
            } else {
                os = new LogOutputStream(this, Project.MSG_INFO);
            }
            Node n = getFragment().getFirstChild();
            if (n == null) {
                throw new BuildException(ERROR_NO_XML);
            }
            writer.write((Element) n, os);
        } catch (BuildException e) {
            throw e;
        } catch (Exception e) {
            throw new BuildException(e);
        } finally {
            FileUtils.close(os);
        }
    }

}