--- a/rep/Editor.java	Wed Oct 01 16:51:01 2008 +0900
+++ b/rep/Editor.java	Wed Oct 01 17:03:20 2008 +0900
@@ -105,7 +105,7 @@
 				return true;
 			}else{
 				System.err.println("Editor.checkReturnedCommand() : command = " + command);
-				assert(false);
+				//assert(false);
 			}
 		}
 		return false;
@@ -125,6 +125,7 @@
 			return true;
 		} else if (quit2!=null && sentList.size()==0) {
 			myChannel.write(quit2);
+			quit2 = null;
 			return true;
 		}
 		return false;

--- a/test/sematest/TestEditor.java	Wed Oct 01 16:51:01 2008 +0900
+++ b/test/sematest/TestEditor.java	Wed Oct 01 17:03:20 2008 +0900
@@ -67,6 +67,9 @@
 	}
 
 	public void run(){
+		/*
+		 * Create Socket and connect to the session manager
+		 */
 		try {
 			channel = REPSocketChannel.<REPCommand>create(new REPCommandPacker());
 		} catch (IOException e) {	return;	}
@@ -79,6 +82,7 @@
 		} catch (IOException e) { return; }
 		ns.writeLog("successes to connect "+name);
 		/*
+		 * Start editor main loop
 		 *         public REPCommand(REP cmd,int sid,int eid, int seq, int lineno,  String string) 
 		 */
 		try {
@@ -87,6 +91,9 @@
 		}
 	}
 
+	/*
+	 * Editor main loop with input lock
+	 */
 	private void mainloop() throws IOException {
 		
 		channel.configureBlocking(false);
@@ -101,7 +108,7 @@
 				continue;
 			} else if (selector.select(timeout)<=0) {
 				if (syncCounter>0) {
-					syncText();
+					syncText(); // send the master editor buffer to clients. 
 				}
 				userInput();
 			} else {
@@ -111,38 +118,53 @@
 	}
 
 	private void syncText() {
+		/*
+		 * Send delete/insert one at a time to synchronize
+		 * all clients. SYNC is requested by the session manager.
+		 */
 		if (syncCounter>text.size()) {
 			syncCounter=0;
 		} else {
 			int i=syncCounter-1;
 			REPCommand del = new REPCommand(REP.REPCMD_DELETE,sid,eid,0,i, text.get(i));
 			REPCommand ins = new REPCommand(REP.REPCMD_INSERT,sid,eid,0,i, text.get(i));
-			sendCommand(del);
-			sendCommand(ins);
+			sendCommand(del,seq++);
+			sendCommand(ins,seq++);
 			syncCounter++;
 		}
 	}
 
+	/*
+	 * Simulate User Input
+	 */
 	private void userInput() {
 		REPCommand cmd = cmds.poll();
 		if (cmd!=null) {
 			switch(cmd.cmd) {
 			case REPCMD_INSERT:
 				text.insert(cmd.lineno, cmd.string);
-				sendCommand(cmd);
+				sendCommand(cmd,seq++);
 				break;
 			case REPCMD_DELETE:
 				String del = text.delete(cmd.lineno);
 				cmd.setString(del);
-				sendCommand(cmd);
+				sendCommand(cmd,seq++);
 				break;
 			case SMCMD_QUIT:
+				/*
+				 * start termination phase 1 by the master editor.
+				 * after this command do not send any user input.
+				 * clients simply disconnect from the session manager.
+				 */
 				cmds.clear();
-				sendCommand(cmd);
+				sendCommand(cmd,cmd.seq++);
 				break;
 			case SMCMD_JOIN:
 			case SMCMD_PUT:
-				sendCommand(cmd);
+				sendCommand(cmd,seq++);
+				/*
+				 * To prevent confusion, stop user input until the ack
+				 */
 				inputLock = true; // wait until ACK
 				break;
 			default:
@@ -155,8 +177,8 @@
 	}
 
 
-	private void sendCommand(REPCommand cmd) {
-		cmd.setSEQID(seq++);
+	private void sendCommand(REPCommand cmd,int seq) {
+		cmd.setSEQID(seq);
 		cmd.setEID(eid);
 		cmd.setSID(sid);
 		ns.writeLog(name +" send "+cmd);
@@ -168,7 +190,7 @@
 		switch(cmd.cmd) {
 		case REPCMD_INSERT	:
 			text.insert(cmd.lineno, cmd.string);
-			sendCommand(cmd);
+			sendCommand(cmd,cmd.seq);
 			// sendCommand(nop); session manager do this for me
 			break;
 		case REPCMD_INSERT_ACK	:
@@ -177,7 +199,7 @@
 		case REPCMD_DELETE	:
 			String del = text.delete(cmd.lineno);
 			cmd.setString(del);
-			sendCommand(cmd);
+			sendCommand(cmd,cmd.seq);
 			// sendCommand(nop); session manager do this for me
 			break;
 		 case REPCMD_DELETE_ACK	:
@@ -188,8 +210,8 @@
 				assert(false);
 			 break;
 		 case REPCMD_NOP		:
-			 sendCommand(cmd);
-			 sendCommand(nop);
+			 sendCommand(cmd,cmd.seq);
+			 sendCommand(nop,seq++);
 			 break;
 		 case SMCMD_JOIN_ACK	:
 			 sid = cmd.sid;
@@ -202,7 +224,7 @@
 			 inputLock = false;
 			 break;
 		 case SMCMD_QUIT		:
-			 sendCommand(cmd);
+			 sendCommand(cmd,seq);
 			 cmds.clear();
 			 break;
 		 case SMCMD_QUIT_ACK	:
@@ -212,7 +234,7 @@
 			 // lock user input during merge (optional)
 			 inputLock = hasInputLock;
 			 cmd.cmd = REP.SMCMD_START_MERGE_ACK;
-			 sendCommand(cmd);
+			 sendCommand(cmd,seq++);
 			 break;
 		 case SMCMD_START_MERGE_ACK :
 			 assert(false);
@@ -221,13 +243,14 @@
 			 inputLock = false;
 			 break;
 		 case SMCMD_QUIT_2 :
-			 sendCommand(cmd);
+			 sendCommand(cmd,cmd.seq);
 			 running = false;
 			 break;
 		 case SMCMD_SYNC:
 			 // start contents sync with newly joined editor
-			 cmd.cmd = REP.SMCMD_SYNC_ACK; sendCommand(cmd);
-			 syncCounter = 1;
+			 cmd.cmd = REP.SMCMD_SYNC_ACK; sendCommand(cmd,cmd.seq);
+			 if (cmd.eid==eid) 
+				 syncCounter = 1;
 			 break;
 		 default:
 			 assert(false);