Adds synchronisation.

joram/a3/rt/src/main/java/fr/dyade/aaa/agent/AgentServer.java

@@ -467,6 +467,12 @@ public final class AgentServer {
     checkServerTask.registerListener(listener);
   }
   
+  public static void unregisterCheckServerListener(CheckServerListener listener) {
+    if (checkServerTask == null)
+      logmon.log(BasicLevel.ERROR, getName() + " cannot unregister CheckServerListener.");
+    checkServerTask.unregisterListener(listener);
+  }
+
   static ThreadGroup tgroup = null;
 
   public static ThreadGroup getThreadGroup() {
@@ -1931,13 +1937,19 @@ class CheckServerTask extends TimerTask {
     listeners = new Vector<CheckServerListener>();
   }
 
-  public void registerListener(CheckServerListener listener) {
+  public synchronized void registerListener(CheckServerListener listener) {
     logmon.log(BasicLevel.INFO,
                AgentServer.getName() + " registers listener for CheckServer.");
     listeners.addElement(listener);
   }
 
-  private void throwListeners() {
+  public synchronized void unregisterListener(CheckServerListener listener) {
+    logmon.log(BasicLevel.INFO,
+               AgentServer.getName() + " unregisters listener for CheckServer.");
+    listeners.removeElement(listener);
+  }
+
+  private synchronized void throwListeners() {
     for (CheckServerListener listener : listeners) {
       logmon.log(BasicLevel.DEBUG,
                  AgentServer.getName() + " calls listener for CheckServer.");
@@ -1982,8 +1994,8 @@ class CheckServerTask extends TimerTask {
     if (! engine.isRunning()) {
       // The engine does not run, just log a warn if needed
       if (((now - lastEngineChangeDate) > dtwarn) && ((now - lastEngineWarnDate) > dtwarn)) {
-        logmon.log(BasicLevel.DEBUG,
-                   AgentServer.getName() + ", engine is not started.");
+        logmon.log(BasicLevel.WARN,
+                   AgentServer.getName() + ", engine is not running.");
         lastEngineWarnDate = now;
       }
       return false;