/* * Copyright (c) 2006-2007 Sun Microsystems, Inc.  All rights reserved. *   *  The Sun Project JXTA(TM) Software License *   *  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 Sun Microsystems, Inc. for JXTA(TM) technology."  *     Alternately, this acknowledgment may appear in the software itself, if  *     and wherever such third-party acknowledgments normally appear. *   *  4. The names "Sun", "Sun Microsystems, Inc.", "JXTA" and "Project JXTA" must  *     not be used to endorse or promote products derived from this software  *     without prior written permission. For written permission, please contact  *     Project JXTA at http://www.jxta.org. *   *  5. Products derived from this software may not be called "JXTA", nor may  *     "JXTA" appear in their name, without prior written permission of Sun. *   *  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 SUN  *  MICROSYSTEMS 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. *   *  JXTA is a registered trademark of Sun Microsystems, Inc. in the United  *  States and other countries. *   *  Please see the license information page at : *  <http://www.jxta.org/project/www/license.html> for instructions on use of  *  the license in source files. *   *  ==================================================================== *   *  This software consists of voluntary contributions made by many individuals  *  on behalf of Project JXTA. For more information on Project JXTA, please see  *  http://www.jxta.org. *   *  This license is based on the BSD license adopted by the Apache Foundation.  */package tutorial.message;import net.jxta.document.AdvertisementFactory;import net.jxta.document.MimeMediaType;import net.jxta.document.StructuredDocumentFactory;import net.jxta.document.XMLDocument;import net.jxta.endpoint.ByteArrayMessageElement;import net.jxta.endpoint.Message;import net.jxta.endpoint.Message.ElementIterator;import net.jxta.endpoint.MessageElement;import net.jxta.endpoint.StringMessageElement;import net.jxta.endpoint.TextDocumentMessageElement;import net.jxta.endpoint.WireFormatMessage;import net.jxta.endpoint.WireFormatMessageFactory;import net.jxta.id.IDFactory;import net.jxta.peergroup.PeerGroupID;import net.jxta.pipe.PipeService;import net.jxta.protocol.PipeAdvertisement;import java.io.ByteArrayOutputStream;import java.io.File;import java.io.IOException;import java.io.InputStream;import java.io.ObjectInputStream;import java.io.ObjectOutputStream;import java.io.RandomAccessFile;import java.util.zip.GZIPInputStream;import java.util.zip.GZIPOutputStream;/** * A simple and re-usable example of manipulating JXATA Messages. Included in * this tutorial are: * <p/> * <ul> * <li>Adding and reading {@code String}, {@code int} and {@code long} with Message elements.</li> * <li>Adding and reading Java {@code Object} with Message Elements. * <li>Adding and reading byte arrays with Message Elements.</li> * <li>Adding and reading JXTA Advertisements with Message Elements.</li> * <li>Compressing message element content with gzip.</li> * </ul> */public class MessageTutorial {    private final static MimeMediaType GZIP_MEDIA_TYPE = new MimeMediaType("application/gzip").intern();    /**     * Adds a String to a Message as a StringMessageElement     *     * @param message   The message to add to     * @param nameSpace The namespace of the element to add. a null value assumes default namespace.     * @param elemName  Name of the Element.     * @param string    The string to add     */    public static void addStringToMessage(Message message, String nameSpace, String elemName, String string) {        message.addMessageElement(nameSpace, new StringMessageElement(elemName, string, null));    }    /**     * Adds a long to a message     *     * @param message   The message to add to     * @param nameSpace The namespace of the element to add. a null value assumes default namespace.     * @param elemName  Name of the Element.     * @param data      The feature to be added to the LongToMessage attribute     */    public static void addLongToMessage(Message message, String nameSpace, String elemName, long data) {        message.addMessageElement(nameSpace, new StringMessageElement(elemName, Long.toString(data), null));    }    /**     * Adds a int to a message     *     * @param message   The message to add to     * @param nameSpace The namespace of the element to add. a null value assumes default namespace.     * @param elemName  Name of the Element.     * @param data      The feature to be added to the IntegerToMessage attribute     */    public static void addIntegerToMessage(Message message, String nameSpace, String elemName, int data) {        message.addMessageElement(nameSpace, new StringMessageElement(elemName, Integer.toString(data), null));    }    /**     * Adds an byte array to a message     *     * @param message   The message to add to     * @param nameSpace The namespace of the element to add. a null value assumes default namespace.     * @param elemName  Name of the Element.     * @param data      the byte array     * @param compress  indicates whether to use GZIP compression     * @throws IOException if an io error occurs     */    public static void addByteArrayToMessage(Message message, String nameSpace, String elemName, byte[] data, boolean compress) throws IOException {        byte[] buffer = data;        MimeMediaType mimeType = MimeMediaType.AOS;        if (compress) {            ByteArrayOutputStream outStream = new ByteArrayOutputStream();            GZIPOutputStream gos = new GZIPOutputStream(outStream);            gos.write(data, 0, data.length);            gos.finish();            gos.close();            buffer = outStream.toByteArray();            mimeType = GZIP_MEDIA_TYPE;        }        message.addMessageElement(nameSpace, new ByteArrayMessageElement(elemName, mimeType, buffer, null));    }    /**     * Adds an Object to message within the specified name space and with the specified element name     * @param message   the message to add the object to     * @param nameSpace the name space to add the object under     * @param elemName  the given element name     * @param object    the object     * @throws IOException if an io error occurs     */    public static void addObjectToMessage(Message message, String nameSpace, String elemName, Object object) throws IOException {        ByteArrayOutputStream bos = new ByteArrayOutputStream();        ObjectOutputStream oos = new ObjectOutputStream(bos);        oos.writeObject(object);        oos.close();        bos.close();        addByteArrayToMessage(message, nameSpace, elemName, bos.toByteArray(), false);    }    /**     * Returns a String from a message     *     * @param message   The message to retrieve from     * @param nameSpace The namespace of the element to get.     * @param elemName  Name of the Element.     * @return The string value or {@code null} if there was no element matching the specified name.     */    public static String getStringFromMessage(Message message, String nameSpace, String elemName) {        MessageElement me = message.getMessageElement(nameSpace, elemName);        if (null != me) {            return me.toString();        } else {            return null;        }    }    /**     * Returns an long from a message     *     * @param message   The message to retrieve from     * @param nameSpace The namespace of the element to get.     * @param elemName  Name of the Element.