re PR libgcj/4859 (java.util.Timer class throw IllegalStateException on cancel())

	Fix for PR libgcj/4859:
	* java/util/Timer.java (TaskQueue.isStopped): New method.
	(Scheduler.run): Don't re-schedule task if queue has been
	stopped.

From-SVN: r46994

libjava/ChangeLog

+2001-11-13  Tom Tromey  <tromey@redhat.com>
+
+	Fix for PR libgcj/4859:
+	* java/util/Timer.java (TaskQueue.isStopped): New method.
+	(Scheduler.run): Don't re-schedule task if queue has been
+	stopped.
+
 2001-11-07  Tom Tromey  <tromey@redhat.com>
 
 	* Makefile.in: Rebuilt.

libjava/java/util/Timer.java

@@ -285,6 +285,14 @@ public class Timer
       this.notify();
     }
 
+    /**
+     * This method returns <code>true</code> if the queue has been
+     * stopped.
+     */
+    public synchronized boolean isStopped ()
+    {
+      return this.heap == null;
+    }
   }				// TaskQueue
 
   /**
@@ -337,8 +345,9 @@ public class Timer
 		}
 	    }
 
-	  // Calculate next time and possibly re-enqueue
-	  if (task.scheduled >= 0)
+	  // Calculate next time and possibly re-enqueue.
+	  // Don't bother re-scheduling if the queue has been stopped.
+	  if (! queue.isStopped () && task.scheduled >= 0)
 	    {
 	      if (task.fixed)
 		{