In-class commenting and improvements

examples/src/TcpExamples/TcpExample4Client.java

@@ -13,13 +13,15 @@ import java.net.*;
  */
 public class TcpExample4Client 
 {
+    static int MAX_LOOP_COUNT = 4;
+    
     public static void main(String[] args) 
     {
         try
         {
-			System.out.println("TcpExample4Client start");
+			System.out.println("TcpExample4Client start, loop " + MAX_LOOP_COUNT + " times");
 			System.out.println("==================================================");
-			for (int loopCount=1; loopCount <= 4; loopCount++) // loop 4 times
+			for (int loopCount=1; loopCount <= MAX_LOOP_COUNT; loopCount++) // loop then exit
 			{
 				System.out.println("TcpExample4Client creating socket #" + loopCount + "...");
 
@@ -32,16 +34,18 @@ public class TcpExample4Client
 				// line after 10 sec.
 				long startTime = System.currentTimeMillis();
 
-				Socket socket = new Socket("localhost", 2317); 
+                // open a socket for each loop
+				Socket socket = new Socket("localhost", 2317);
 
-				// Read the single line written by the server. We'd
-				// do things a bit differently if many lines to be read
+				// Setup.  Read the single line written by the server.
+				// We'd do things a bit differently if many lines to be read
 				// from the server, instead of one only.
 				InputStream       is  = socket.getInputStream();
 				InputStreamReader isr = new InputStreamReader(is);
 				BufferedReader     br = new BufferedReader(isr);
-
-				String serverMessage = br.readLine();
+System.out.println("client point 1...");
+				String serverMessage = br.readLine(); // blocks?
+System.out.println("client point 2...");
 				long   readTime = System.currentTimeMillis();
 				long timeLength = readTime - startTime;
 
@@ -51,6 +55,7 @@ public class TcpExample4Client
 				// To push this further, launch multiple copies of TcpExample4Client simultaneously
 			}
 			System.out.println("TcpExample4Client complete");
+            // main method now exits
         }
         catch(IOException e)
         {

examples/src/TcpExamples/TcpExample4HandlerThread.java

-
-
 package TcpExamples;
 
 import java.io.*;
@@ -47,11 +45,12 @@ public class TcpExample4HandlerThread extends Thread
 
 			 final long TIMEOUT = 2000; // 2000 milliseconds = 2 seconds, 10000 milliseconds = 10 seconds
 			 System.out.println("TcpExample4HandlerThread pausing for TIMEOUT=" + TIMEOUT + "ms"); // debug
-             Thread.sleep(TIMEOUT); // 10 seconds
+             Thread.sleep(TIMEOUT);
                 
+            // ps is the PrintStream is the Java way to use System.print() to pass data along the socket.
             ps.println("This message was written by the server TcpExample4HandlerThread");
-            ps.flush();
-            socket.close();
+            ps.flush();     // make sure that it indeed escapes current process and reaches the client
+            socket.close(); // all clear, no longer need socket
             System.out.println("TcpExample4HandlerThread finished handling a thread, now exit.");
         }
         catch(IOException | InterruptedException e) // either a networking or a threading problem

examples/src/TcpExamples/TcpExample4TerminalLog.txt

@@ -3,15 +3,16 @@ Invocation instructions:
 2. don't run TcpExample4HandlerThread since it is launched as needed
 3. run/debug TcpExample4Client.java
 
-Program responses:
+Two program response logs:
 
+===================================================
 ===================================================
 run:
 TcpExample4ThreadServer ready to accept socket connections...
 =============================================================
 TcpExample4ThreadServer.handlerThread invocation for connection #1...
-TcpExample4ThreadServer.handlerThread is launched, awaiting another connection...
-TcpExample4HandlerThread starting to handle a thread...
+TcpExample4ThreadServer.handlerThread is launched, awaiting another connection...T
+cpExample4HandlerThread starting to handle a thread...
 TcpExample4HandlerThread pausing for TIMEOUT=10000ms
 TcpExample4HandlerThread finished handling a thread, now exit.
 =============================================================
@@ -34,6 +35,7 @@ TcpExample4HandlerThread pausing for TIMEOUT=10000ms
 TcpExample4HandlerThread finished handling a thread, now exit.
 BUILD STOPPED (total time: 1 minute 7 seconds)
 
+===================================================
 ===================================================
 run:
 TcpExample4Client start
@@ -56,3 +58,6 @@ TcpExample4Client: time msec required for read=10003
 ==================================================
 TcpExample4Client complete
 BUILD SUCCESSFUL (total time: 40 seconds)
+
+===================================================
+===================================================
\ No newline at end of file