cms.java

jxta-cms-src-2.4.zip 是官网上的比较稳定的CMS源代码。目前是最稳定的高版本。

/*
 * Copyright (c) 2001 Sun Microsystems, Inc.  All rights
 * reserved.
 *
 * 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 the
 *       Sun Microsystems, Inc. for Project JXTA."
 *    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 THE APACHE SOFTWARE FOUNDATION 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.
 *
 *====================================================================
 *
 * 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.
 *
 * $Id: CMS.java,v 1.30 2006/02/07 20:43:49 bondolo Exp $
 *
 */

package net.jxta.share;

import java.io.File;
import java.io.InputStream;
import java.io.IOException;

import net.jxta.discovery.DiscoveryService;
import net.jxta.document.Advertisement;
import net.jxta.document.MimeMediaType;
import net.jxta.endpoint.EndpointService;
import net.jxta.endpoint.EndpointAddress;
import net.jxta.endpoint.EndpointListener;
import net.jxta.endpoint.Message;
import net.jxta.endpoint.MessageElement;
import net.jxta.endpoint.ByteArrayMessageElement;
import net.jxta.exception.PeerGroupException;
import net.jxta.id.ID;
import net.jxta.peergroup.PeerGroup;
import net.jxta.platform.Application;
import net.jxta.protocol.ResolverQueryMsg;
import net.jxta.protocol.ResolverResponseMsg;
import net.jxta.resolver.ResolverService;
import net.jxta.resolver.QueryHandler;


import org.apache.log4j.Logger;
import org.apache.log4j.Level;

/**
 * This class implements the Content Management Service.
 * The class is started with one of the startApp methods.
 * The command pipe and persistent directory is passed to the startApp method, else
 * default values are used.
 * A remote client interacts with the service by finding the request PipeAdvertisement
 * and sending it LIST and GET requests. The requests are handled by the 
 * ListMessageProcessor and GetMessageProcessor.
 */

public class CMS implements Application, EndpointListener, QueryHandler {

    private final static transient Logger LOG = Logger.getLogger(CMS.class.getName());

    public static final String DEFAULT_DIR = "cms";

    // Message tag's
    public static final String LIST_REQUEST = "LIST_REQ";
    public static final String LIST_RESULT = "LIST_RES";
    public static final String GET_REQUEST = "GET_REQ";
    public static final String GET_RESULT = "GET_RES";

    public static final String MESSAGE_TYPE = "msgType";
    public static final String REQUEST_ID = "RID";
    public static final String CONTENT_ID = "CID";
    public static final String RETURN_ADDRESS = "RTN_ADR";
    public static final String CONTENT_ADVERTISEMENT = "CADV";
    public static final String CONTENT_LENGTH = "CLEN";
    public static final String ADVERTISEMENT_COUNT = "COUNT";
    public static final String CHUNK_OFFSET = "OFFSET";
    public static final String CHUNK_SIZE = "SIZE";
    public static final String CHUNK_DATA = "DATA";
    public static final String RANGE_BEGIN = "RANGE_BEGIN";
    public static final String RANGE_END = "RANGE_END";

    public static final String QUERY_SUBSTRING = "QSUBSTR";

    public static String serviceName = "CMS";
    public static MimeMediaType encodeAs = new MimeMediaType("text", "xml");


    // The following two constants defines how long ContentAdvertisements are published
    // in Discovery.
    // FIXME: 11/03/2002 [e-mail] We need to have a better lifecycle management
    // of the advertisements. Current settings are probably fine for usual usage of CMS
    // for the time being.

    private static long DEFAULT_LOCAL_ADV_LIFETIME = DiscoveryService.DEFAULT_LIFETIME;
    private static long DEFAULT_REMOTE_ADV_LIFETIME = 2 * 60 * 1000L; // 2 minutes

    private PeerGroup group = null;
    private ListMessageProcessor listQueue = null;
    private GetMessageProcessor getQueue = null;
    private ContentManager contentManager = null;
    private File cmsDir = null;


    public CMS() {
        // Set the default content manager directory to a subdirectory of the
        // JXTA_HOME directory.
        String homedir = System.getProperty("JXTA_HOME");
        homedir = (homedir != null) ? homedir + DEFAULT_DIR : DEFAULT_DIR;
        cmsDir = new File(homedir);

        if (LOG.isEnabledFor(Level.INFO))
            LOG.info("create new CMS");
        // Makes sure the AdvertisementFactory knows about ContentAdvertisement
        ContentAdvertisementImpl.registerAdvertisement();
    }

    /**
     * Initialize the application passing it ist peer group handle.
     *
     * @param group PeerGroup this application is started from
     *
     * @exception PeerGroupException failure to initialize the peer group application
     *
     */

    public void init(PeerGroup group,
                     ID assignedID,
                     Advertisement impl)
    throws PeerGroupException {

        this.group = group;
    }
    /**
     * Start the service with the given parameters.
     * The parameters are in the form of name=value pairs.
     * There is one optional parameter, the directory for storing
     * persistent data about the shared content.  
     *
     * @param arg String[] of parameters
     *
     * @return int status indication. 0 if ok, -1 if error
     */
    public int startApp(String[] arg) {
        File cmsDir = null;

        for (int i=0; i<arg.length; i++) {
            // Directory parameter
            if (arg[i].startsWith("dir=")) {
                cmsDir = new File(arg[i].substring(4));
            }
        }

        return startApp(cmsDir);
    }

    /**
     * Start the service with the given parameters.
     *
     * @param rPipeAdv PipeAdvertisement of the request pipe
     * @param cmsDir File pointing to the persistence directory
     *
     * @return int status indication. 0 if ok, -1 if error.
     */
    public int startApp(File dir) {
        // check if a cmsDir was passed
        if(dir != null)
            cmsDir = dir;

        // Check if the cms directory exists
        if (false == cmsDir.exists()) {
            // create the directory
            cmsDir.mkdir();
        }

        // Initialize the content manager
        try {
            contentManager = new ContentManagerImpl(cmsDir, this);
        } catch (IOException e) {
            if (LOG.isEnabledFor(Level.ERROR))
                LOG.error("Could not initialize content manager");
            return (-1);
        }

        // initialize the message processor queues
        listQueue = new ListMessageProcessor(this);
        getQueue = new GetMessageProcessor(this);

        // register the message listener
        group.getEndpointService().addIncomingMessageListener(this,serviceName, getGroupId(group));
        // Publish the contentManager
        publishAllContents ();

        return 0;
    }

    /**
     * Stops the service
     */
    public void stopApp() {
        // unregister the message listener
        group.getEndpointService().removeIncomingMessageListener(serviceName, getGroupId(group));

        group.getResolverService().unregisterHandler(serviceName + getGroupId (group));
    }

    /**
     * Add a SearchListener object to monitor the search queries recieved.
     *
     * @param sl the SearchListener to add
     * @see SearchListener
     * @see #removeSearchListener(SearchListener)
     */
    public void addSearchListener(SearchListener sl) {
        if(listQueue != null)
            listQueue.addSearchListener(sl);