endpointrouter.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

/************************************************************************
 *
<<<<<<< EndpointRouter.java
 * $Id: EndpointRouter.java,v 1.117 2002/06/26 21:10:51 bondolo Exp $
=======
 * $Id: EndpointRouter.java,v 1.117 2002/06/26 21:10:51 bondolo Exp $
>>>>>>> 1.114.2.1
 *
 * 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.
 *********************************************************************************/

package net.jxta.impl.endpoint;

import net.jxta.endpoint.*;
import net.jxta.document.*;
import net.jxta.peergroup.*;
import net.jxta.discovery.*;
import net.jxta.id.*;
import net.jxta.protocol.*;
import net.jxta.resolver.*;
import net.jxta.exception.*;
import net.jxta.peer.PeerID;

import net.jxta.impl.util.*;
import net.jxta.impl.protocol.*;
import net.jxta.impl.discovery.*;

import java.io.*;
import java.util.*;
import java.net.URL;
import org.apache.log4j.Category;
import org.apache.log4j.Priority;

import net.jxta.platform.Module;

public class EndpointRouter implements EndpointProtocol,
QueryHandler,
EndpointListener,
Module {
  
  protected class Route {
    public String dest = null;
    public String router = null;
    public int    nbOfHops = 0;
    public Vector gateways = null;
    
    public Route(String dest,
    String router,
    int nbOfHops,
    Vector gateways) {
      this.dest = dest;
      this.router = router;
      this.nbOfHops = nbOfHops;
      this.gateways = gateways;
    }
    
    public void display() {
      if (LOG.isEnabledFor(Priority.DEBUG)) LOG.debug("Route to    = " + dest);
      if (LOG.isEnabledFor(Priority.DEBUG)) LOG.debug("    nextHop = " + router);
      if (gateways == null) {
        if (LOG.isEnabledFor(Priority.DEBUG)) LOG.debug("    no gateways");
      } else {
        for (int i=0; i < gateways.size(); ++i) {
          try {
            if (LOG.isEnabledFor(Priority.DEBUG)) LOG.debug("   [" + i + "] " + (String) gateways.elementAt(i));
          } catch (Exception ez1) {
          }
        }
      }
    }
  }
  
  private static final Category LOG = Category.getInstance(EndpointRouter.class.getName());
  
  /**
   * Key is a peer id.  Value is a Route
   */
  private Hashtable routedRoutes = null;
  
  /**
   * These are peers we can reach directly (ping).<BR>
   * Key is peer id.  Value is address.
   */
  private Hashtable directRoutes = null;
  
  // As a stringified endpointAddress.
  protected String localPeerAddr = null;
  
  protected ID localPeerId = null;
  
  private EndpointService endpoint = null;
  // XXX: MaxTTL should be a configurable. For the time being
  // rely on the seven levels of separation.
  // [e-mail]
  //    private static final int MaxTTL = 7;
  private DiscoveryService discovery = null;
  private PeerGroup group = null;
  private static final String TypeTag = "Type";
  private static final String RoutingPeerIdTag = "RoutingPeer";
  private static final String RoutingPeerAdvTag = "RoutingPeerAdv";
  private static final String DestPeerIdTag = "DestPeer";
  private static final String NbOfHopsTag = "NbOfHops";
  public  static final String GatewayForwardTag = "GatewayForward";
  public  static final String GatewayReverseTag = "GatewayReverse";
  private static final String VersionTag = "Version";
  private static final String RouteQuery = "RouteQuery";
  private static final String RouteResponse = "RouteResponse";
  private static final String PingQuery = "PingQuery";
  private static final String PingResponse = "PingResponse";
  private static final String NACK = "NACK";
  private static final int    acceptableVersion = 3;
  private static final int    currentVersion = 3;
  private ResolverService resolver = null;
  private boolean servicesInitialized = false;
  private int qid = 0;
  
  private static final String routerSName = "EndpointRouter";
  private static String routerSParam = null;
  private EndpointAdvertisement myAdv = null;
  private String localPeerAdv = null;
  protected Vector localGateway = new Vector(1);
  
  // Until we decide otherwise, the router is *by definition* handling
  // peerID addressed messages.
  private static String routerPName = "jxta";
  
  // This is not good enough to avoid redundant queries because
  // we remove them as soon as they've been sent (no timer),
  // but at least it avoids infinite recursions if we're looking
  // for the route to a rendezvous (queries try to go there).
  private Vector pendingQueries = new Vector();
  
  public EndpointRouter() {
  }
  
  /**
   * Returns true if this protocol accepts to be overloaded.
   * That is let a protocol with the name protocol name in a
   * descendant group be registered.
   *
   * @return boolean true if over load is allowed.
   */
  public boolean allowOverLoad() {
    return true;
  }
  
  /**
   * Make this protocol as up and running.
   * When this method is called, all the services are already registered
   * with the peergroup. So we do not need to delay binding any further.
   * All the public methods, which could be called between init and startApp
   * are defensive regarding the services possibly not being there.
   */
  public int startApp(String[] arg) {
    
    discovery = group.getDiscoveryService();
    resolver = group.getResolverService();
    
    if( null == discovery )
      if (LOG.isEnabledFor(Priority.WARN)) LOG.warn( "discovery service is not available!" );
    
    if( null == resolver )
      if (LOG.isEnabledFor(Priority.WARN)) LOG.warn( "resolver service is not available!" );
    
    resolver.registerHandler(routerSName, this);
    
    return 0;
  }
  
  /**
   * closes this EndpointProtocol.
   * Carefull that stopApp() could in theory be called before startApp().
   */
  public void stopApp() {
    if (resolver != null) resolver.unregisterHandler(routerSName);
    if (endpoint != null) {
      endpoint.removeListener(routerSName + routerSParam, this);
      endpoint.removeEndpointProtocol(this);
    }
  }
  
  public void init( PeerGroup g, ID assignedID, Advertisement impl)
  throws PeerGroupException {
    
    group = g;
    endpoint = g.getEndpointService();
    localPeerAdv = advToString(g.getPeerAdvertisement());
    localPeerId = g.getPeerID();
    localPeerAddr = routerPName
    + "://"
    + group.getPeerID().getUniqueValue().toString();
    routerSParam = g.getPeerGroupID().getUniqueValue().toString();
    
    try {
      localGateway.add(0, localPeerAddr);
    } catch (Exception ez1) {
      if (LOG.isEnabledFor(Priority.WARN)) LOG.warn("Cannot set myself as a gateway");
    }
    if (LOG.isEnabledFor(Priority.DEBUG)) LOG.debug("localPeerId = " + localPeerId);
    
    directRoutes = new Hashtable();
    routedRoutes = new Hashtable();
    
    // We're ready for our methods to be called; even if they won't
    // be of much help until startApp().
    endpoint.addListener(routerSName + routerSParam, this);
    endpoint.addEndpointProtocol(this);
  }
  
  public boolean isConnectionOriented() {
    return false;
  }
  
  /**
   * Returns true if the endpoint protocol can be used by the EndpointRouter
   *
   * @return boolean true if the protocol can be used by the EndpointRouter
   */
  public boolean allowRouting() {
    // Yes, this is the router, and it does not allow routing.
    // Otherwise we would have a chicken and egg problem.
    return false;
  }
  /**
   * Return the endpoint address by which this peer is accessible via this
   * transport.
   */
  public EndpointAddress getPublicAddress() {
    return endpoint.newEndpointAddress(localPeerAddr);
  }
  
  /**
   * Returns the address family that this endpoint protocol handles.
   * This endpoint protocol handles the address family that denotes
   * peerId's.
   *
   * @return String the endpoint protocol name
   */
  public String getProtocolName() {
    return routerPName;
  }
  
  public void propagate(Message srcMsg,
  String pName,
  String pParam,
  String prunePeer) throws IOException {
    
    // All messages are lost in the ether
  }
  
  /**
   * closes this EndpointProtocol.
   */
  public void close() {
    endpoint.removeListener(routerSName + routerSParam, this);
  }
  
  /**
   *  convert a doc to string
   *
   * @param  adv  Description of Parameter
   * @return      Description of the Returned Value
   * @since
   */
  private String advToString(Advertisement adv) {
    
    StringWriter out = new StringWriter();
    MimeMediaType displayAs = new MimeMediaType("text/xml");
    
    try {
      StructuredTextDocument doc = (StructuredTextDocument) adv.getDocument(displayAs);
      doc.sendToWriter(out);
      return out.toString();
    } catch (Exception all) {
      return null;
    }
  }
  
  public Enumeration getPeerAdv(String pId) {
    
    if (LOG.isEnabledFor(Priority.DEBUG)) LOG.debug("getPeerAdv for : " + pId);
    if (discovery == null) {
      if (LOG.isEnabledFor(Priority.DEBUG)) LOG.debug("  no discovery");
      return null;
    }
    
    // What we refer to in the router as PeerIDs, are generaly not
    // peerIDs, they're endpoint addresses based on a peer ID.
    try {
      EndpointAddress asAddress = endpoint.newEndpointAddress(pId);
       URL asUrl = IDFactory.jxtaURL( net.jxta.id.ID.URIEncodingName, 
                         "",
			 net.jxta.id.ID.URNNamespace  + ":"
			 + asAddress.getProtocolAddress());

      String realPeerID = asUrl.toString();
      return discovery.getLocalAdvertisements(DiscoveryService.PEER,
      "PID",
      realPeerID);
    } catch (Exception e) {
      if (LOG.isEnabledFor(Priority.DEBUG)) LOG.debug("  failed with " + e);
      return null;
    }
  }
  
  private synchronized void waitABit() {
    
    // We'll still wake if something interresting happens.
    try {
      wait(500);
    } catch (Exception e) {
      if (LOG.isEnabledFor(Priority.DEBUG))
        LOG.debug("getAddress got an exception " + e + " while waiting", e);
    }
  }
  
  /**
   * Give a peer id, return an address to reach that peer.
   * The address may be for a directly reachable peer, or
   * for the first gateway along a route to reach the peer.
   * If we do not have a route to the peer, we will use the