[cooja/serialsocket] SeriaSocketServer: Moved Observer and Handler to inner classes and let handler thread join before notifying server terminated

tools/cooja/apps/serial_socket/java/org/contikios/cooja/serialsocket/SerialSocketServer.java

@@ -111,8 +111,6 @@ public class SerialSocketServer extends VisPlugin implements MotePlugin {
 
   private ServerSocket serverSocket;
   private Socket clientSocket;
-  private DataInputStream in;
-  private DataOutputStream out;
 
   private Mote mote;
 
@@ -282,13 +280,15 @@ public class SerialSocketServer extends VisPlugin implements MotePlugin {
             @Override
             public void run() {
               socketStatusLabel.setForeground(COLOR_POSITIVE);
-              socketStatusLabel.setText(String.format("Client " + client.getInetAddress() + " connected."));
+              socketStatusLabel.setText("Client "
+                      + client.getInetAddress() + ":" + client.getPort()
+                      + " connected.");
             }
           });
         }
 
         @Override
-        public void onClientDisconnected(final Socket client) {
+        public void onClientDisconnected() {
           SwingUtilities.invokeLater(new Runnable() {
 
             @Override
@@ -338,7 +338,7 @@ public class SerialSocketServer extends VisPlugin implements MotePlugin {
   public interface ServerListener {
     void onServerStarted(int port);
     void onClientConnected(Socket client);
-    void onClientDisconnected(Socket client);
+    void onClientDisconnected();
     void onServerStopped();
     void onServerError(String msg);
   }
@@ -359,9 +359,9 @@ public class SerialSocketServer extends VisPlugin implements MotePlugin {
     }
   }
 
-  public void notifyClientDisconnected(Socket client) {
+  public void notifyClientDisconnected() {
     for (ServerListener listener : listeners) {
-      listener.onClientDisconnected(client);
+      listener.onClientDisconnected();
     }
   }
   
@@ -393,6 +393,7 @@ public class SerialSocketServer extends VisPlugin implements MotePlugin {
     }
 
     new Thread() {
+      private Thread incomingDataHandler;
       @Override
       public void run() {
         while (!serverSocket.isClosed()) {
@@ -409,31 +410,13 @@ public class SerialSocketServer extends VisPlugin implements MotePlugin {
 
             clientSocket = candidateSocket;
 
-            in = new DataInputStream(clientSocket.getInputStream());
-            out = new DataOutputStream(clientSocket.getOutputStream());
-            out.flush();
-            startSocketReadThread(in);
+            /* Start handler for data input from socket */
+            incomingDataHandler = new Thread(new IncomingDataHandler());
+            incomingDataHandler.start();
 
             /* Observe serial port for outgoing data */
-            serialPort.addSerialDataObserver(serialDataObserver = new Observer() {
-              @Override
-              public void update(Observable obs, Object obj) {
-                try {
-                  if (out == null) {
-                    /*logger.debug("out is null");*/
-                    return;
-                  }
-
-                  out.write(serialPort.getLastSerialData());
-                  out.flush();
-
-                  outBytes++;
-                } catch (IOException ex) {
-                  logger.error(ex);
-                  cleanupClient();
-                }
-              }
-            });
+            serialDataObserver = new SerialDataObserver();
+            serialPort.addSerialDataObserver(serialDataObserver);
 
             inBytes = outBytes = 0;
 
@@ -450,6 +433,14 @@ public class SerialSocketServer extends VisPlugin implements MotePlugin {
           }
         }
         cleanupClient();
+        if (incomingDataHandler != null) {
+          // Wait for reader thread to terminate
+          try {
+            incomingDataHandler.join(500);
+          } catch (InterruptedException ex) {
+            logger.warn(ex);
+          }
+        }
         notifyServerStopped();
       }
     }.start();
@@ -466,13 +457,22 @@ public class SerialSocketServer extends VisPlugin implements MotePlugin {
     }
   }
 
-  private void startSocketReadThread(final DataInputStream in) {
   /* Forward data: virtual port -> mote */
-    Thread incomingDataThread = new Thread(new Runnable() {
+  private class IncomingDataHandler implements Runnable {
+
+    DataInputStream in;
+
     @Override
     public void run() {
       int numRead = 0;
       byte[] data = new byte[1024];
+      try {
+        in = new DataInputStream(clientSocket.getInputStream());
+      } catch (IOException ex) {
+        logger.error(ex);
+        return;
+      }
+
       logger.info("Forwarder: socket -> serial port");
       while (numRead >= 0) {
         for (int i = 0; i < numRead; i++) {
@@ -490,8 +490,39 @@ public class SerialSocketServer extends VisPlugin implements MotePlugin {
       logger.info("End of Stream");
       cleanupClient();
     }
-    });
-    incomingDataThread.start();
+  }
+
+  private class SerialDataObserver implements Observer {
+    
+    DataOutputStream out;
+
+    public SerialDataObserver() {
+      try {
+        out = new DataOutputStream(clientSocket.getOutputStream());
+      } catch (IOException ex) {
+        logger.error(ex);
+        out = null;
+      }
+    }
+
+    @Override
+    public void update(Observable obs, Object obj) {
+      try {
+        if (out == null) {
+          /*logger.debug("out is null");*/
+          return;
+        }
+
+        out.write(serialPort.getLastSerialData());
+        out.flush();
+
+        outBytes++;
+      } catch (IOException ex) {
+        logger.error(ex);
+        cleanupClient();
+      }
+    }
+
   }
 
   @Override
@@ -572,25 +603,10 @@ public class SerialSocketServer extends VisPlugin implements MotePlugin {
     } catch (IOException e1) {
       logger.error(e1.getMessage());
     }
-    try {
-      if (in != null) {
-        in.close();
-        in = null;
-      }
-    } catch (IOException e) {
-      logger.error(e.getMessage());
-    }
-    try {
-      if (out != null) {
-        out.close();
-        out = null;
-      }
-    } catch (IOException e) {
-      logger.error(e.getMessage());
-    }
+
     serialPort.deleteSerialDataObserver(serialDataObserver);
 
-    notifyClientDisconnected(null);
+    notifyClientDisconnected();
   }
 
   private boolean closed = false;