2003/11/13 05:04:22

[org.ibex.core.git] / src / org / xwt / Scheduler.java

diff --git a/src/org/xwt/Scheduler.java b/src/org/xwt/Scheduler.java
index a46c75c..79fba3c 100644 (file)
--- a/src/org/xwt/Scheduler.java
+++ b/src/org/xwt/Scheduler.java
@@ -10,34 +10,35 @@ public class Scheduler {
 
     // Public API Exposed to org.xwt /////////////////////////////////////////////////
 
+    private static Scheduler singleton;
     public static abstract class Task { public abstract void perform(); }
     public static void add(Task t) { singleton.runnable.append(t); }
-    public static void init() { singleton.run(); }
+    public static void init() {
+        if (singleton != null) return;
+        singleton = Platform.getScheduler();
+        singleton.run();
+    }
 
 
     // API which must be supported by subclasses /////////////////////////////////////
 
-    protected Scheduler() { }
-
     /**
-     *  INVARIANT: all scheduler implementations MUST invoke
-     *  Surface.renderAll() after performing a Task if no tasks remain
-     *  in the queue.  A scheduler may choose to invoke
-     *  Surface.renderAll() more often than that if it so chooses.
+     *  INVARIANT: all scheduler implementations MUST invoke Surface.renderAll() after performing a Task if no tasks remain
+     *  in the queue.  A scheduler may choose to invoke Surface.renderAll() more often than that if it so chooses.
      */
     public void run() { defaultRun(); }
+    protected Scheduler() { }
 
 
-    // Default Implementation /////////////////////////////////////
+    // Default Implementation //////////////////////////////////////////////////////
 
     protected static Queue runnable = new Queue(50);
-    private static final Scheduler singleton = Platform.getScheduler();
     public void defaultRun() {
         while(true) {
             Task t = (Task)runnable.remove(true);
             try {
                 t.perform();
-                // FIXME: be smarter about this
+                // FEATURE: be smarter about this
                 Surface.renderAll();
             } catch (Exception e) {
                 Log.log(Scheduler.class, "Task threw an exception: " + e);