adding ping and pong

5 files changed, 75 insertions, 3 deletions

diff --git a/src/Ivy.java b/src/Ivy.java
index 7e14619..7d26dff 100755
--- a/src/Ivy.java
+++ b/src/Ivy.java
@@ -112,7 +112,7 @@ public class Ivy implements Runnable {
    * the library version, useful for development purposes only, when java is
    * invoked with -DIVY_DEBUG
    */
-  public static final String libVersion ="1.2.11";
+  public static final String libVersion ="1.2.12";
 
   private boolean debug;
   private ServerSocket app;
diff --git a/src/IvyClient.java b/src/IvyClient.java
index 85edfc8..5e71ccb 100755
--- a/src/IvyClient.java
+++ b/src/IvyClient.java
@@ -10,6 +10,8 @@
  * created for each remote client.
  *
  *  CHANGELOG:
+ *  1.2.12
+ *  - Ping and Pong are back ...
  *  1.2.8
  *  - no CheckRegexp anymore
  *  - synchronized(regexps) pour le match et le getParen():
@@ -90,6 +92,8 @@ public class IvyClient implements Runnable {
   final static int SchizoToken = 6; /* avoid race condition in concurrent connexions, aka BeginRegexp in other implementations */
   final static int DirectMsg = 7;/* the peer sends a direct message */
   final static int Die = 8;  /* the peer wants us to quit */
+  final static int Ping = 9;  // from outer space
+  final static int Pong = 10;  
   final static String MESSAGE_TERMINATOR = "\n"; /* the next protocol will use \r */
   final static String StartArg = "\u0002";/* begin of arguments */
   final static String EndArg = "\u0003"; /* end of arguments */
@@ -101,6 +105,7 @@ public class IvyClient implements Runnable {
   // private variables
   private static Integer csMutex=new Integer(0);
   private static int clientSerial=0;	/* an unique ID for each IvyClient */
+  private Stack PCHStack = new Stack();
   
   private String messages_classes[] = null;
   private Ivy bus;
@@ -234,6 +239,16 @@ public class IvyClient implements Runnable {
     sendString(Die,0,message);
   }
 
+  /**
+   * triggers a Ping, and executes the callback
+   * @param  pc the callback that will be triggerred (once) when the ponc is
+   * received
+   */
+  public void ping(PingCallback pc) throws IvyException {
+    PCHStack.push(new PingCallbackHolder(pc));
+    sendString(Ping,0,"");
+  }
+
   ///////////////////////////////////////////////////
   //
   // PROTECTED METHODS
@@ -471,6 +486,12 @@ public class IvyClient implements Runnable {
 	  throw new IvyException(ioe.getMessage());
 	}
 	break;
+      case Pong:
+        ((PingCallbackHolder)PCHStack.pop()).run();
+	break;
+      case Ping:
+	sendString(Pong,0,"");
+	break;
       case AddRegexp:
 	String regexp=s.substring(from,b.length);
 	if ( bus.CheckRegexp(regexp) ) {
@@ -569,4 +590,17 @@ public class IvyClient implements Runnable {
     traceDebug(s);
   }
 
+  private class PingCallbackHolder {
+    PingCallback pc;
+    long epoch;
+    PingCallbackHolder(PingCallback pc) {
+      this.pc=pc;
+      epoch=System.currentTimeMillis();
+      PCHStack.push(this);
+    }
+    void run() {
+      pc.pongReceived(IvyClient.this,(int)(System.currentTimeMillis()-epoch));
+    }
+  }
+
 }
diff --git a/src/Makefile b/src/Makefile
index ecf9e33..1d89856 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -2,7 +2,7 @@ include ../java.mk
 
 #.SUFFIXES: .java .class
      #SRCS = *.java
-     SRCS = IvyApplicationAdapter.java IvyApplicationListener.java IvyBindListener.java IvyClient.java IvyException.java Ivy.java IvyMessageListener.java IvyWatcher.java SelfIvyClient.java WaiterClient.java Waiter.java 
+     SRCS = IvyApplicationAdapter.java IvyApplicationListener.java IvyBindListener.java IvyClient.java IvyException.java Ivy.java IvyMessageListener.java IvyWatcher.java SelfIvyClient.java WaiterClient.java Waiter.java PingCallback.java
      TOOLS= IvyDaemon.java Probe.java After.java
 
      OBJS = $(SRCS:.java=.class)
diff --git a/src/PingCallback.java b/src/PingCallback.java
new file mode 100644
index 0000000..ff3233b
--- /dev/null
+++ b/src/PingCallback.java
@@ -0,0 +1,20 @@
+package fr.dgac.ivy;
+
+/**
+ * this interface specifies the methods of an PingCallback
+ *
+ * @author	Yannick Jestin
+ * @author	<a href="http://www.tls.cena.fr/products/ivy/">http://www.tls.cena.fr/products/ivy/</a>
+ *
+ * Changelog:
+ * 1.2.12
+ */
+
+public interface PingCallback {
+  /**
+   * invoked when a Pong is received
+   * @param elapsedTime the elapsed time in milliseconds between the ping and
+   * the pong
+   */
+  void pongReceived(IvyClient ic,int elapsedTime);
+}
diff --git a/src/Probe.java b/src/Probe.java
index 0d3eed7..8ced8e5 100644
--- a/src/Probe.java
+++ b/src/Probe.java
@@ -7,6 +7,8 @@
  * (c) CENA
  *
  * Changelog:
+ * 1.2.12
+ *   - .ping is back
  * 1.2.9
  *   - added the .time command
  *   - added the .bound *
@@ -71,7 +73,8 @@ public class Probe implements IvyApplicationListener, IvyMessageListener, IvyBin
   ".bound CLIENT\t\t\t* lists the subscriptions of a client, .bound * to get all\n"+
   ".bound\t\t\t\t* lists the probe's subscriptions\n"+
   ".where CLIENT\t\t\t* displays the host where a client runs\n"+
-  ".time COUNT MESSAGE\t\t\t* measures the time it takes to send COUNT messages\n"
+  ".time COUNT MESSAGE\t\t\t* measures the time it takes to send COUNT messages\n"+
+  ".ping CLIENT\t\t\t* measures the roundtrip time in millisecond to reach a client\n"
   ;
 
   public static final String helpmsg =
@@ -274,6 +277,21 @@ public class Probe implements IvyApplicationListener, IvyMessageListener, IvyBin
       for (int i=0;i<v.size();i++) {
 	println("-> "+((IvyClient)v.elementAt(i)).getApplicationName());
       }
+    } else if ( s.lastIndexOf(".ping ")>=0) {
+      String target=s.substring(6);
+      Vector v=bus.getIvyClientsByName(target);
+      if (v.size()==0) println("no Ivy client with  the name \""+target+"\"");
+      for (int i=0;i<v.size();i++) {
+	try {
+	  ((IvyClient)v.elementAt(i)).ping(new PingCallback() {
+	  public void pongReceived(IvyClient ic,int elapsedTime){
+	  System.out.println("round trip to"+ic.getApplicationName()+" "+elapsedTime+" ms");
+	  }
+	  });
+	} catch (IvyException ie) {
+	  println("-> ping not sent, the remote client must have disconnected");
+	}
+      }
     } else if ( s.lastIndexOf(".where ")>=0) {
       String target=s.substring(7);
       Vector v=bus.getIvyClientsByName(target);