Author: mrogers
Date: 2006-09-14 14:13:08 +0000 (Thu, 14 Sep 2006)
New Revision: 10464
Added:
trunk/apps/load-balancing-sims/phase6/MessageHandler.java
Log:
CHK inserts, sorry about the large number of commits, I accidentally added
classfiles to the repository and I'm trying to fix it
Added: trunk/apps/load-balancing-sims/phase6/MessageHandler.java
===================================================================
--- trunk/apps/load-balancing-sims/phase6/MessageHandler.java 2006-09-14
14:13:05 UTC (rev 10463)
+++ trunk/apps/load-balancing-sims/phase6/MessageHandler.java 2006-09-14
14:13:08 UTC (rev 10464)
@@ -0,0 +1,69 @@
+// The state of a search as stored at each node along the path
+
+import java.util.LinkedList;
+import messages.Search;
+import messages.Message;
+
+abstract class MessageHandler
+{
+ // State machine
+ protected final static int STARTED = 0;
+ protected final static int SENT = 1;
+ protected final static int ACCEPTED = 2;
+ protected final static int TRANSFERRING = 3;
+ protected final static int COMPLETED = 4;
+
+ protected final int id; // The unique ID of the request or insert
+ protected final int key; // The target of the search
+ protected double closest; // The closest location seen so far
+ protected int htl; // Hops to live for backtracking
+
+ protected Node node; // The owner of this MessageHandler
+ protected Peer prev; // The previous hop of the search
+ protected Peer next = null; // The (current) next hop of the search
+ protected LinkedList<Peer> nexts; // Candidates for the next hop
+
+ public MessageHandler (Search s, Node node, Peer prev)
+ {
+ id = s.id;
+ key = s.key;
+ closest = s.closest;
+ htl = s.htl;
+ this.node = node;
+ this.prev = prev;
+ nexts = new LinkedList<Peer> (node.peers());
+ nexts.remove (prev);
+ // If this is the closest location seen so far, reset htl
+ double target = Node.keyToLocation (key);
+ if (Node.distance (target, node.location)
+ < Node.distance (target, closest)) {
+ node.log ("resetting htl of " + this);
+ closest = node.location;
+ htl = Search.MAX_HTL;
+ }
+ }
+
+ // Remove a peer from the list of candidates for the next hop
+ public void removeNextHop (Peer p)
+ {
+ nexts.remove (p);
+ }
+
+ // Find the closest remaining peer
+ protected Peer closestPeer ()
+ {
+ double keyLoc = Node.keyToLocation (key);
+ double closestDist = Double.POSITIVE_INFINITY;
+ Peer closestPeer = null;
+ for (Peer peer : nexts) {
+ double dist = Node.distance (keyLoc, peer.location);
+ if (dist < closestDist) {
+ closestDist = dist;
+ closestPeer = peer;
+ }
+ }
+ return closestPeer; // Null if the list was empty
+ }
+
+ public abstract void handleMessage (Message m, Peer src);
+}
