Broke out the places where we actually read from/write to the channels into

separate methods so that we can override them to do crazy stuff like simulate
latency/dropped packets for debugging.


git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@6072 542714f4-19e9-0310-aa3c-eee0fc999fb1

src/java/com/threerings/presents/client/BlockingCommunicator.java

@@ -395,7 +395,7 @@ public class BlockingCommunicator extends Communicator
                 String txt = StringUtil.truncate(String.valueOf(msg), 80, "...");
                 log.info("Whoa, writin' a big one", "msg", txt, "size", buffer.limit());
             }
-            int wrote = _channel.write(buffer);
+            int wrote = writeMessage(buffer);
             if (wrote != buffer.limit()) {
                 log.warning("Aiya! Couldn't write entire message", "msg", msg,
                             "size", buffer.limit(), "wrote", wrote);
@@ -412,6 +412,17 @@ public class BlockingCommunicator extends Communicator
         updateWriteStamp();
     }
 
+    /**
+     * Writes the message contained in the supplied buffer.
+     *
+     * @return the number of bytes written.
+     */
+    protected int writeMessage (ByteBuffer buf)
+        throws IOException
+    {
+        return _channel.write(buf);
+    }
+
     /**
      * Sends a datagram over the datagram socket.
      */
@@ -444,12 +455,23 @@ public class BlockingCommunicator extends Communicator
         buf.put(hash, 0, 8).rewind();
 
         // send the datagram
-        _datagramChannel.write(buf);
+        writeDatagram(buf);
 
         // notify the tracker
         _client.getMessageTracker().messageSent(true, size, msg);
     }
 
+    /**
+     * Writes the datagram contained in the supplied buffer.
+     *
+     * @return the number of bytes written.
+     */
+    protected int writeDatagram (ByteBuffer buf)
+        throws IOException
+    {
+        return _datagramChannel.write(buf);
+    }
+
     /**
      * Reads a new message from the socket (blocking until a message has arrived).
      */
@@ -460,7 +482,7 @@ public class BlockingCommunicator extends Communicator
         // of the frame from the network, in which case we simply call it again because we can't do
         // anything until it has a whole frame; it will throw an exception if it hits EOF or if
         // something goes awry)
-        while (!_fin.readFrame(_channel)) {
+        while (!readFrame()) {
             // noop!
         }
 
@@ -479,6 +501,17 @@ public class BlockingCommunicator extends Communicator
         }
     }
 
+    /**
+     * Reads a frame from the socket.
+     *
+     * @return true if a complete frame is available, false if more needs to be read.
+     */
+    protected boolean readFrame ()
+        throws IOException
+    {
+        return _fin.readFrame(_channel);
+    }
+
     /**
      * Reads a datagram from the socket (blocking until a datagram has arrived).
      */
@@ -487,7 +520,7 @@ public class BlockingCommunicator extends Communicator
     {
         // clear the buffer and read a datagram
         _buf.clear();
-        int size = _datagramChannel.read(_buf);
+        int size = readDatagram(_buf);
         if (size <= 0) {
             throw new IOException("No datagram available to read.");
         }
@@ -514,6 +547,17 @@ public class BlockingCommunicator extends Communicator
         }
     }
 
+    /**
+     * Reads a datagram into the supplied buffer.
+     *
+     * @return the number of bytes read.
+     */
+    protected int readDatagram (ByteBuffer buf)
+        throws IOException
+    {
+        return _datagramChannel.read(buf);
+    }
+
     protected void openChannel (InetAddress host)
         throws IOException
     {