From f5eba59b191c77ae8f6a957d9296b70815cd37f7 Mon Sep 17 00:00:00 2001
From: senft-desktop <senftt@gmail.com>
Date: Thu, 29 Nov 2012 19:56:22 +0100
Subject: [PATCH] Send/receive status

---
 ws2012/P2P/uebungen/4/src/node/Node.java      | 16 +++++-
 .../P2P/uebungen/4/src/node/UDPHandler.java   | 53 ++++++++++++-------
 2 files changed, 50 insertions(+), 19 deletions(-)

diff --git a/ws2012/P2P/uebungen/4/src/node/Node.java b/ws2012/P2P/uebungen/4/src/node/Node.java
index 5ca61392..eada9491 100644
--- a/ws2012/P2P/uebungen/4/src/node/Node.java
+++ b/ws2012/P2P/uebungen/4/src/node/Node.java
@@ -202,6 +202,20 @@ public class Node {
         }
     }
 
+    protected void sendStatus(InetSocketAddress reveiver) {
+        ByteBuffer buffer = ByteBuffer.allocate(BUF_SIZE);
+        buffer.put(MessageType.STATUS);
+        for (SocketAddress n : neighbors) {
+            buffer.put(BufferUtil.addrToBytes((InetSocketAddress) n));
+        }
+
+        try {
+            channel.send(buffer, reveiver);
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+
     public void gatherInformationOfNetwork() {
         byte[] myAddr;
         try {
@@ -222,7 +236,7 @@ public class Node {
     protected Ack getAck(int ack_id) {
         return acks.get(ack_id);
     }
-    
+
     protected Ack removeAck(int ack_id) {
         return acks.remove(ack_id);
     }
diff --git a/ws2012/P2P/uebungen/4/src/node/UDPHandler.java b/ws2012/P2P/uebungen/4/src/node/UDPHandler.java
index dfec8155..b30e691b 100644
--- a/ws2012/P2P/uebungen/4/src/node/UDPHandler.java
+++ b/ws2012/P2P/uebungen/4/src/node/UDPHandler.java
@@ -4,7 +4,9 @@ import java.io.IOException;
 import java.net.InetSocketAddress;
 import java.net.SocketAddress;
 import java.nio.ByteBuffer;
+import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Map;
 import java.util.logging.Level;
 import java.util.logging.Logger;
@@ -31,7 +33,7 @@ public class UDPHandler implements Runnable {
     }
 
     private void receiveInvite(SocketAddress from) {
-        LOGGER.log(Level.INFO, "{0} received invite from {1}", new Object[] {
+        LOGGER.log(Level.INFO, "{0}: received invite from {1}", new Object[] {
                 node.getName(), from.toString() });
         int ack_id = buf.getInt();
         node.sendAck(from, ack_id);
@@ -41,7 +43,8 @@ public class UDPHandler implements Runnable {
     private void receiveAck(SocketAddress from) {
         int ack_id = buf.getInt();
 
-        LOGGER.log(Level.INFO, "{0} received ack ({1}) from {2}", new Object[] {
+        LOGGER.log(Level.INFO, "{0}: received ack ({1}) from {2}",
+                new Object[] {
                 node.getName(), ack_id, from.toString() });
 
         if (node.hasAck(ack_id)) {
@@ -54,17 +57,6 @@ public class UDPHandler implements Runnable {
         }
     }
 
-    private boolean isNewBroadcast(int id) {
-        boolean isNew = true;
-        if (broadcastPackets.containsKey(id)) {
-            long receivedAt = broadcastPackets.get(id);
-            if (receivedAt < System.currentTimeMillis() + BROADCAST_TIMEOUT) {
-                isNew = false;
-            }
-        }
-        return isNew;
-    }
-
     private void receiveLeave(SocketAddress from) {
         LOGGER.log(Level.INFO, "{0}: {1} is leaving. Deleting...",
                 new Object[] { node.getName(), from.toString() });
@@ -81,6 +73,7 @@ public class UDPHandler implements Runnable {
         int packet_id = buf.getInt();
         byte command = buf.get();
         if (isNewBroadcast(packet_id)) {
+            // Save packet id so we don't forward a packet multiple times
             broadcastPackets.put(packet_id, System.currentTimeMillis());
 
             switch (command) {
@@ -97,7 +90,7 @@ public class UDPHandler implements Runnable {
                         new Object[] { node.getName(), from.toString(),
                                 originalSender.toString() });
 
-                // TODO: Answer with 'my' neighbors
+                node.sendStatus(originalSender);
 
                 break;
             default:
@@ -110,11 +103,21 @@ public class UDPHandler implements Runnable {
             }
         } else {
             LOGGER.log(Level.INFO,
-                    "Received duplicate broadcast packet ({0}). Discarding...",
-                    new Object[] { packet_id });
+                    "{0}: Received duplicate broadcast packet ({0}). Discarding...",
+                    new Object[] { node.getName(), packet_id });
         }
     }
 
+    private void receiveStatus(SocketAddress receivedFrom) {
+        List<SocketAddress> neighbors = new ArrayList<SocketAddress>();
+
+        while (buf.hasRemaining()) {
+            neighbors.add(readIPFromBuffer());
+        }
+
+        // Keep track of all neighbors..
+    }
+
     private InetSocketAddress readIPFromBuffer() {
         StringBuilder theAddr = new StringBuilder();
         // Read 4 Bytes and 1 Integer = 1 IP address
@@ -138,13 +141,24 @@ public class UDPHandler implements Runnable {
 
         LOGGER.log(
                 Level.INFO,
-                "{0} from {1} received new neighbor:{2}",
+                "{0}: from {1} received new neighbor:{2}",
                 new Object[] { node.getName(), from.toString(),
                         newNeighbor.toString() });
 
         node.sendAck(from, ack_id);
     }
 
+    private boolean isNewBroadcast(int id) {
+        boolean isNew = true;
+        if (broadcastPackets.containsKey(id)) {
+            long receivedAt = broadcastPackets.get(id);
+            if (receivedAt < System.currentTimeMillis() + BROADCAST_TIMEOUT) {
+                isNew = false;
+            }
+        }
+        return isNew;
+    }
+
     public void run() {
         SocketAddress receivedFrom = null;
 
@@ -175,10 +189,13 @@ public class UDPHandler implements Runnable {
                     case MessageType.BROADCAST:
                         receiveBroadcast(receivedFrom);
                         break;
+                    case MessageType.STATUS:
+                        receiveStatus(receivedFrom);
+                        break;
                     default:
                         LOGGER.log(
                                 Level.INFO,
-                                "{0} received unknown command from {1}: [{2}]{3}",
+                                "{0}: received unknown command from {1}: [{2}]{3}",
                                 new Object[] { node.getName(),
                                         receivedFrom.toString(), messageType,
                                         new String(buf.array()) });