remoting/android/java/src/org/chromium/chromoting/SessionConnector.java

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 package org.chromium.chromoting;
   6
   7 import org.chromium.chromoting.jni.JniInterface;
   8
   9 /**
  10  * This class manages making a connection to a host, with logic for reloading the host list and
  11  * retrying the connection in the case of a stale host JID.
  12  */
  13 public class SessionConnector implements JniInterface.ConnectionListener,
  14         HostListLoader.Callback {
  15     private JniInterface.ConnectionListener mConnectionCallback;
  16     private HostListLoader.Callback mHostListCallback;
  17     private HostListLoader mHostListLoader;
  18     private SessionAuthenticator mAuthenticator;
  19
  20     private String mAccountName;
  21     private String mAuthToken;
  22
  23     /** Used to find the HostInfo from the returned array after the host list is reloaded. */
  24     private String mHostId;
  25
  26     private String mHostJabberId;
  27
  28     /**
  29      * Tracks whether the connection has been established. Auto-reloading and reconnecting should
  30      * only happen if connection has not yet occurred.
  31      */
  32     private boolean mConnected;
  33
  34     /**
  35      * @param connectionCallback Object to be notified on connection success/failure.
  36      * @param hostListCallback Object to be notified whenever the host list is reloaded.
  37      * @param hostListLoader The object used for reloading the host list.
  38      */
  39     public SessionConnector(JniInterface.ConnectionListener connectionCallback,
  40             HostListLoader.Callback hostListCallback, HostListLoader hostListLoader) {
  41         mConnectionCallback = connectionCallback;
  42         mHostListCallback = hostListCallback;
  43         mHostListLoader = hostListLoader;
  44     }
  45
  46     /** Initiates a connection to the host. */
  47     public void connectToHost(String accountName, String authToken, HostInfo host,
  48             SessionAuthenticator authenticator) {
  49         mAccountName = accountName;
  50         mAuthToken = authToken;
  51         mHostId = host.id;
  52         mHostJabberId = host.jabberId;
  53         mAuthenticator = authenticator;
  54
  55         if (hostIncomplete(host)) {
  56             // These keys might not be present in a newly-registered host, so treat this as a
  57             // connection failure and reload the host list.
  58             reloadHostListAndConnect();
  59             return;
  60         }
  61
  62         JniInterface.connectToHost(accountName, authToken, host.jabberId, host.id, host.publicKey,
  63                 this, mAuthenticator);
  64     }
  65
  66     private static boolean hostIncomplete(HostInfo host) {
  67         return host.jabberId.isEmpty() || host.publicKey.isEmpty();
  68     }
  69
  70     private void reloadHostListAndConnect() {
  71         mHostListLoader.retrieveHostList(mAuthToken, this);
  72     }
  73
  74     @Override
  75     public void onConnectionState(JniInterface.ConnectionListener.State state,
  76             JniInterface.ConnectionListener.Error error) {
  77         boolean connected = mConnected;
  78         mConnected = (state == JniInterface.ConnectionListener.State.CONNECTED);
  79
  80         if (!connected && state == JniInterface.ConnectionListener.State.FAILED
  81                 && error == JniInterface.ConnectionListener.Error.PEER_IS_OFFLINE) {
  82             // The host is offline, which may mean the JID is out of date, so refresh the host list
  83             // and try to connect again.
  84             reloadHostListAndConnect();
  85         } else {
  86             // Pass the state/error back to the caller.
  87             mConnectionCallback.onConnectionState(state, error);
  88         }
  89     }
  90
  91     @Override
  92     public void onHostListReceived(HostInfo[] hosts) {
  93         // Notify the caller, so the UI is updated.
  94         mHostListCallback.onHostListReceived(hosts);
  95
  96         HostInfo foundHost = null;
  97         for (HostInfo host : hosts) {
  98             if (host.id.equals(mHostId)) {
  99                 foundHost = host;
 100                 break;
 101             }
 102         }
 103
 104         if (foundHost == null || foundHost.jabberId.equals(mHostJabberId)
 105                 || hostIncomplete(foundHost)) {
 106             // Cannot reconnect to this host, or there's no point in trying because the JID is
 107             // unchanged, so report the original failure to the client.
 108             mConnectionCallback.onConnectionState(JniInterface.ConnectionListener.State.FAILED,
 109                     JniInterface.ConnectionListener.Error.PEER_IS_OFFLINE);
 110         } else {
 111             // Reconnect to the host, but use the original callback directly, instead of this
 112             // wrapper object, so the host list is not loaded again.
 113             JniInterface.connectToHost(mAccountName, mAuthToken, foundHost.jabberId,
 114                     foundHost.id, foundHost.publicKey, mConnectionCallback, mAuthenticator);
 115         }
 116     }
 117
 118     @Override
 119     public void onError(HostListLoader.Error error) {
 120         // Connection failed and reloading the host list also failed, so report the connection
 121         // error.
 122         mConnectionCallback.onConnectionState(JniInterface.ConnectionListener.State.FAILED,
 123                 JniInterface.ConnectionListener.Error.PEER_IS_OFFLINE);
 124
 125         // Notify the caller that the host list failed to load, so the UI is updated accordingly.
 126         // The currently-displayed host list is not likely to be valid any more.
 127         mHostListCallback.onError(error);
 128     }
 129 }