implemented automatic reverse connections with GRPL message type

git-svn-id: svn://anubis/gvsu@60 45c1a28c-8058-47b2-ae61-ca45b979098e

cs654/proj1/KaZaGUI.java

@@ -181,7 +181,8 @@ public class KaZaGUI extends JFrame
                 if (m_server != null)
                 {
                     m_server.connectToPeerGroupLeader(
-                            m_serverPeerAddressField.getText());
+                            m_serverPeerAddressField.getText(),
+                            true);
                     m_serverPeerAddressField.setText("");
                 }
             }

cs654/proj1/KaZaServer.java

@@ -38,19 +38,34 @@ public class KaZaServer implements Runnable
         }
     }
 
-    public void connectToPeerGroupLeader(String peerName)
+    public void connectToPeerGroupLeader(String peerName,
+                                         boolean sendReverseConnectMsg)
     {
+        /* check if the peer group leader is already in our list */
+        synchronized (m_peerGroupLeaders)
+        {
+            for (Socket s : m_peerGroupLeaders)
+            {
+                if (s.getInetAddress().getHostAddress().equals(peerName))
+                    return;
+            }
+        }
+
         Socket s;
         try
         {
             s = new Socket(peerName, LISTEN_PORT);
             DataOutputStream os = new DataOutputStream(s.getOutputStream());
             os.writeBytes("HELO KaZaServer\n");
+            if (sendReverseConnectMsg)
+                os.writeBytes("GRPL\n");
         }
         catch (Exception e)
         {
             return;
         }
+
+        /* add new peer group leader to the peer group leaders list */
         synchronized (m_peerGroupLeaders)
         {
             m_peerGroupLeaders.add(s);
@@ -193,6 +208,12 @@ public class KaZaServer implements Runnable
                         m_socket.close();
                         running = false;
                     }
+                    else if (opCode.equals("GRPL"))
+                    {
+                        /* user is a peer group leader, initiate a connection
+                         * to it if one is not established */
+                        connectToPeerGroupLeader(m_clientIP, false);
+                    }
                 }
             }
             catch (Exception e) { }