resolverserviceimpl.java

jxme的一些相关程序,主要是手机上程序开发以及手机和计算机通信的一些程序资料,程序编译需要Ant支持

/*
 * 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 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.
 * ====================================================================
 *
 * 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: ResolverServiceImpl.java,v 1.20 2002/06/18 20:46:01 hamada Exp $
 */
package net.jxta.impl.resolver;

import java.util.Enumeration;
import java.util.Vector;
import java.util.Hashtable;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;

import org.apache.log4j.Category;
import org.apache.log4j.Priority;

import net.jxta.credential.Credential;
import net.jxta.credential.AuthenticationCredential;
import net.jxta.membership.Authenticator;
import net.jxta.membership.MembershipService;
import net.jxta.document.Advertisement;
import net.jxta.document.AdvertisementFactory;
import net.jxta.document.Document;
import net.jxta.document.MimeMediaType;
import net.jxta.document.StructuredDocument;
import net.jxta.endpoint.EndpointService;
import net.jxta.endpoint.EndpointAddress;
import net.jxta.endpoint.EndpointListener;
import net.jxta.endpoint.EndpointMessenger;
import net.jxta.endpoint.Message;
import net.jxta.endpoint.MessageElement;
import net.jxta.endpoint.MessageElementEnumeration;
import net.jxta.exception.DiscardQueryException;
import net.jxta.exception.NoResponseException;
import net.jxta.exception.PeerGroupException;
import net.jxta.exception.ResendQueryException;
import net.jxta.exception.ServiceNotFoundException;
import net.jxta.id.ID;
import net.jxta.id.IDFactory;
import net.jxta.peer.PeerID;
import net.jxta.peergroup.PeerGroup;
import net.jxta.protocol.ModuleImplAdvertisement;
import net.jxta.protocol.ResolverQueryMsg;
import net.jxta.protocol.ResolverResponseMsg;
import net.jxta.rendezvous.RendezVousService;
import net.jxta.resolver.QueryHandler;
import net.jxta.resolver.ResolverService;
import net.jxta.service.Service;
import net.jxta.util.StringEnumeration;

import net.jxta.impl.rendezvous.RendezVousPropagateMessage;
import net.jxta.impl.protocol.ResolverQuery;
import net.jxta.impl.protocol.ResolverResponse;


/**
 * ResolverService Service provides a generic mechanism for jxta Services
 * to send "Queries", and receive "Responses".  It removes the burden for
 * registered handlers in deal with :
 *
 *   - Setting message tags, to ensure uniqueness of tags and
 *     ensures that messages are sent to correct address, and group
 *   - Authentication, and Verification of credentials
 *   - drop rogue messages
 *
 * ResolverService Service does not proccess the queries, nor does it not compose
 * reponses. Handling of queries, and composition of responses are left up
 * to the registered handlers. Services that wish to handle queries,
 * and generate reponses must implement <Code>QueryHandler<Code>
 *
 * Message Format :
 *
 * A Query message
 *
 * <?xml version="1.0" standalone='yes'?>
 * <ResolverQuery>
 *   <handlername> name </handlername>
 *   <credential> uri </credential>
 *   <queryid> id </queryid>
 *   <query> query </query>
 * </ResolverQuery>
 *
 * Note: queryid is unique to the originating node only, it can be utilized to
 * match queries to responses.
 *
 * A Response Message
 *
 * <?xml version="1.0" standalone='yes'?>
 * <ResolverResponse>
 *   <handlername> name </handlername>
 *   <credential> uri </credential>
 *   <queryid> id </queryid>
 *   <response> response </response>
 * </ResolverResponse>
 *
 * Note: queryid is unique to the originating node only, it can be
 * utilized to match queries to responses
 *
 * @see net.jxta.protocol.ResolverQueryMsg;
 * @see net.jxta.protocol.ResolverResponseMsg;
 * @since JXTA 1.0
 */

public class ResolverServiceImpl implements ResolverService, EndpointListener {
    
    private static final Category LOG =
    Category.getInstance(ResolverServiceImpl.class.getName());
    
    public  static final String outQueNameShort="ORes";
    public  static final String  inQueNameShort="IRes";
    public  String outQueName="ORes";
    public  String  inQueName="IRes";
    private EndpointService endpoint;
    private Hashtable handlers = new Hashtable(50);
    private PeerGroup myGroup=null;
    private String localPeerId = null;
    private RendezVousService rendezvous = null;
    private MembershipService membership = null;
    private Credential credential = null;
    private StructuredDocument credentialDoc = null;
    private ModuleImplAdvertisement implAdvertisement = null;
    private RecvDemux recvMux = null;
    private String handlerName = null;
    private MimeMediaType textXml = new MimeMediaType("text/xml");

    // Until we make a factory for this
    private EndpointAddress mkAddress(String destPeer,
    String serv, String parm) {
        try {
            PeerID asID = (PeerID) IDFactory.fromURL(IDFactory.jxtaURL(destPeer));
            String asString = "jxta://" + asID.getUniqueValue().toString();
            
            EndpointAddress addr = endpoint.newEndpointAddress(asString);
            addr.setServiceName(serv);
            addr.setServiceParameter(parm);
            return addr;
        }
        catch (Exception e) {
            if (LOG.isEnabledFor(Priority.WARN))
                LOG.warn("Invalid peerID string " + destPeer);
		throw new RuntimeException("Error creating Peer Address :" +e.toString());
        }
    }
    
    /**
     * Default constructor
     */
    public ResolverServiceImpl( ) {
        
    }
    
    /**
     * Supply arguments and starts this service if it hadn't started by itself.
     *
     * Currently this service starts by itself and does not expect
     * arguments.
     *
     * @param arg A table of strings arguments.
     * @return int status indication.
     */
    public int startApp(String[] arg) {
        rendezvous        = myGroup.getRendezVousService();
	membership        = myGroup.getMembershipService();

        try {
            rendezvous.addPropagateListener(handlerName + outQueName,
	                                    this);
            rendezvous.addPropagateListener(handlerName + inQueName,
	                                    recvMux);
        }
        catch (Exception e) {
            if (LOG.isEnabledFor(Priority.ERROR)) {
                LOG.error("failed to add listeners", e );
	    }
            return 1;
        }
	
	try {
		Enumeration enum = membership.getCurrentCredentials();
		if (enum.hasMoreElements()) {
		    // get the only credential "nobody"
		    credential = (Credential)enum.nextElement();
		    credentialDoc = credential.getDocument(textXml);
		} 
        } catch (Exception e) {
            if (LOG.isEnabledFor(Priority.ERROR)) {
                LOG.error("failed to get credential", e );
	    }
        }

        return 0;
    }
    
    /**
     * Ask this service to stop.
     *
     * let's detach from the endpoint
     */
    public void stopApp() {
        try {
            rendezvous.removePropagateListener(handlerName + outQueName,
	                                       this);
            rendezvous.removePropagateListener(handlerName + inQueName,
	                                       recvMux);
        }
        catch (Exception e) {
            if (LOG.isEnabledFor(Priority.ERROR)) {
                LOG.error("failed to detach from the Rendezvous Service", e );
	    }
        }
    }
    
    /**
     * Service objects are not manipulated directly to protect usage
     * of the service. A Service interface is returned to access the service
     * methods.
     *
     * @return Service public interface of the service
     *
     * @since JXTA 1.0
     */
    public Service getInterface() {
        return new ResolverServiceInterface(this);
    }
    
    
    /**
     * Returns the advertisement for that service.
     *
     * @return Advertisement the advertisement.
     *
     * @since JXTA 1.0
     */
    public Advertisement getImplAdvertisement() {
        return implAdvertisement;
    }
    
    /**
     * Registers the given ResolveHandler.
     *
     * @param name The name under which this handler is known.
     * @param handler The handler.
     * @return The previous handler registered under this name
     */
    public synchronized QueryHandler registerHandler( String name, QueryHandler handler ) {
   
     return (QueryHandler)handlers.put( name, handler );
    }
    
    /**
     * unregisters the given ResolveHandler.
     *
     * @param name The name under which this handler is known.
     * @param handler The handler.
     * @return The previous handler registered under this name
     */
    public synchronized QueryHandler unregisterHandler( String name ) {
        return (QueryHandler) handlers.remove(name);
    }
    
    /**
     * gets the handler registered under the given name.
     * @param name Handler name
     * @return ResolveHandler
     */
    public QueryHandler getHandler(String name) {
        return (QueryHandler) handlers.get(name);
    }
    
    /**
     * try getting a response for our query
     * @param address
     * @param query
     * @throws RuntimeException
     **/
    public void sendQuery(String rdvPeer, ResolverQueryMsg query) {
	
        if (rendezvous == null)
            return;
        
        if (LOG.isEnabledFor(Priority.DEBUG))
            LOG.debug("sending query");
        
        ResolverResponse doc=null;
        Message propagateMsg = endpoint.newMessage();
        
        if (rdvPeer == null) {
            try {
                propagateMsg.addElement(
                propagateMsg.newMessageElement(outQueName,
                                               textXml,
					       (InputStream)((Document)
					       (query.getDocument(textXml))).getStream()));
                
                rendezvous.propagateInGroup(propagateMsg,
                                            handlerName,
					    outQueName,
					    7,
					    null);
            }
            catch (Exception e) {
                if (LOG.isEnabledFor(Priority.INFO)) {
                    LOG.info( "Error during propagate" ,e);
		}
                throw new RuntimeException("Error during propagate :" +e.toString());
            }
        }
        else {
            
            //unicast instead
            try {
                respond(rdvPeer,
                        handlerName,
			outQueName,
			outQueName,
			((Document)(query.getDocument(textXml))).getStream());
            }
            catch (Exception e) {
                if (LOG.isEnabledFor(Priority.INFO)) {
                    LOG.info( "Error while unicasting query :", e );
		}
                throw new RuntimeException("Error while unicasting query :" +e.toString());
            }
        }
    }
    
    
        /*
         * Returns the group to which this service is attached.
         * @return PeerGroup the group
         */
    public PeerGroup getGroup() {
        return((PeerGroup)myGroup);
    }
    
    
    private void propagateQuery(Message msg) {
        
        if (rendezvous == null)
            return;
        
        if (!myGroup.isRendezvous()) {
            // We are not a Rendez vous peer. Just drop the message.
            return;
        }
        
        // We are a Rendez vous. Re-propagate the message.
        // Loop and TTL control is done in demux and propagate(). The TTL 7
        // below is just a default it will be reduced appropriately
        
        try {
            rendezvous.propagateInGroup(msg,
                                        handlerName,
					outQueName,
					7,
					localPeerId);
        }