Implement master functionality.

- The first participant in the network is considered the master.
- Forward join requests to the master.

3 files changed, 59 insertions, 15 deletions

diff --git a/jsonrpc/src/main/java/com/orbekk/same/SameService.java b/jsonrpc/src/main/java/com/orbekk/same/SameService.java
index 0db9698..9e1071d 100644
--- a/jsonrpc/src/main/java/com/orbekk/same/SameService.java
+++ b/jsonrpc/src/main/java/com/orbekk/same/SameService.java
@@ -20,6 +20,6 @@ public interface SameService {
     /**
      * Notification of participation in network.
      */
-    void notifyParticipation(String networkName,
+    void notifyParticipation(String networkName, String masterId,
             Map<String, String> participants);
 }
diff --git a/jsonrpc/src/main/java/com/orbekk/same/SameServiceImpl.java b/jsonrpc/src/main/java/com/orbekk/same/SameServiceImpl.java
index 7e61a2d..0e17f54 100644
--- a/jsonrpc/src/main/java/com/orbekk/same/SameServiceImpl.java
+++ b/jsonrpc/src/main/java/com/orbekk/same/SameServiceImpl.java
@@ -35,9 +35,9 @@ public class SameServiceImpl implements SameService {
     }
 
     @Override
-    public void notifyParticipation(String networkName,
+    public void notifyParticipation(String networkName, String masterId,
             Map<String, String> participants) {
-        logger.info("Joining network {}.", networkName);
+        logger.info("Joining network {}. Master is {}", networkName, masterId);
         int i = 1;
         for (Map.Entry<String, String> e : participants.entrySet()) {
             String clientId = e.getKey();
@@ -46,6 +46,6 @@ public class SameServiceImpl implements SameService {
                     new Object[]{networkName, i, clientId, url});
             i++;
         }
-        logger.warn("Joining not implemented.");
+        sameState.joinNetwork(networkName, masterId, participants);
     }
 }
diff --git a/jsonrpc/src/main/java/com/orbekk/same/SameState.java b/jsonrpc/src/main/java/com/orbekk/same/SameState.java
index cd1c84a..c3d03f9 100644
--- a/jsonrpc/src/main/java/com/orbekk/same/SameState.java
+++ b/jsonrpc/src/main/java/com/orbekk/same/SameState.java
@@ -19,6 +19,18 @@ public class SameState extends Thread implements UrlReceiver {
     private String networkName;
 
     /**
+     * The master participant id.
+     */
+    private String masterId;
+
+    /**
+     * TODO: Remove.
+     */
+    public void setMasterId(String masterId) {
+        this.masterId = masterId;
+    }
+
+    /**
      * The participants of this network.
      *
      * Maps clientId to url.
@@ -43,6 +55,7 @@ public class SameState extends Thread implements UrlReceiver {
         this.networkName = networkName;
         this.clientId = clientId;
         this.connections = connections;
+        this.masterId = clientId;
         participants.put(clientId, null);
     }
 
@@ -55,6 +68,24 @@ public class SameState extends Thread implements UrlReceiver {
         return participants;
     }
 
+    /**
+     * Reset this SameService to an initial state.
+     *
+     * TODO: Implement fully.
+     */
+    private synchronized void resetState() {
+        pendingParticipants.clear();
+    }
+
+    public synchronized void joinNetwork(String networkName, String masterId,
+            Map<String, String> participants) {
+        resetState();
+        this.networkName = networkName;
+        this.masterId = masterId;
+        this.participants = participants;
+        logger.info("Joined network {}.", networkName);
+    }
+
     public String getClientId() {
         return clientId;
     }
@@ -83,18 +114,31 @@ public class SameState extends Thread implements UrlReceiver {
         notifyAll();
     }
 
+    private boolean isMaster() {
+        return masterId.equals(clientId);
+    }
+
     private synchronized void handleNewParticipants() {
-        // Adding all pending participants ensures that each of the new
-        // participants is informed of all participants.
-        //
-        // TODO: Does not inform old participants.
-        participants.putAll(pendingParticipants);
-        for (Map.Entry<String, String> e : pendingParticipants.entrySet()) {
-            String clientId = e.getKey();
-            String url = e.getValue();
-            logger.info("New participant: {} URL({})", clientId, url);
-            SameService remoteService = connections.getConnection(url);
-            remoteService.notifyParticipation(networkName, participants);
+        if (!isMaster()) {
+            for (Map.Entry<String, String> e : pendingParticipants.entrySet()) {
+                SameService master = connections.getConnection(
+                        participants.get(masterId));
+                logger.info("Redirecting participant request to {}", masterId);
+                String clientId = e.getKey();
+                String url = e.getValue();
+                master.participateNetwork(networkName, clientId, url);
+            }
+        } else {
+            participants.putAll(pendingParticipants);
+            for (Map.Entry<String, String> e :
+                    pendingParticipants.entrySet()) {
+                String clientId = e.getKey();
+                String url = e.getValue();
+                logger.info("New participant: {} URL({})", clientId, url);
+                SameService remoteService = connections.getConnection(url);
+                remoteService.notifyParticipation(networkName, masterId,
+                        participants);
+            }
         }
         pendingParticipants.clear();
     }