Fix Bug 606 - New AWT threading implementation breaks .. ; Fix GLAutoDrawable multi-threading w/ proper pattern (hope so)

Considering code changes and remarks:
  3ed491213f8f7f05d7b9866b50d764370d8ff5f6
  1a91ec5c8b6fd9d9db7bc115569c369fe7b38e9b
  3334a924309a9361a448d69bc707d4cce416b430
  4f27bcecf7484dc041551f52a5c49e2884cb3867

It seems necessary to have

- recursive locking employed for all semantic actions which changes drawable & context (and the Window resource)

- to avoid deadlock, we have to ensure the locked code segment will not spawn
  off to another thread, or a thread holds the lock, spawns of an action requiring the lock. .. sure

- other read-only methods (flags, ..) shall at least utilize a safe local copy of a volatile field
  if further use to produce the result is necessary.

- flags like sendReshape require to be volatile to guarantee it's being processed

Patch impacts: AWT/SWT GLCanvas, GLAutoDrawableBase [and it's specializations]
and hopefully closes any loopholes of missing a cache hit, etc.

If you review this and find optimizations, i.e. removing a lock due to semantics etc,
don't hold back and discuss it, please.

1 files changed, 17 insertions, 27 deletions

diff --git a/src/jogl/classes/javax/media/opengl/GLAutoDrawableDelegate.java b/src/jogl/classes/javax/media/opengl/GLAutoDrawableDelegate.java
index 1f6166719..76959f3f4 100644
--- a/src/jogl/classes/javax/media/opengl/GLAutoDrawableDelegate.java
+++ b/src/jogl/classes/javax/media/opengl/GLAutoDrawableDelegate.java
@@ -67,18 +67,18 @@ public class GLAutoDrawableDelegate extends GLAutoDrawableBase {
     }
     
     //
-    // make protected methods accessible
+    // expose default methods
     //
     
-    public void defaultWindowRepaintOp() {
+    public final void windowRepaintOp() {
         super.defaultWindowRepaintOp();
     }
     
-    public void defaultWindowResizedOp() {
+    public final void windowResizedOp() {
         super.defaultWindowResizedOp();
     }
     
-    public void defaultWindowDestroyNotifyOp() {
+    public final void windowDestroyNotifyOp() {
         super.defaultWindowDestroyNotifyOp();
     }
     
@@ -90,6 +90,9 @@ public class GLAutoDrawableDelegate extends GLAutoDrawableBase {
     private final Object upstreamWidget;
     
     @Override
+    protected final RecursiveLock getLock() { return lock; }
+    
+    @Override
     public final Object getUpstreamWidget() {
         return upstreamWidget;
     }
@@ -97,39 +100,21 @@ public class GLAutoDrawableDelegate extends GLAutoDrawableBase {
     /**
      * {@inheritDoc}
      * <p>
-     * This implementation calls {@link #defaultDestroyOp()}.
+     * This implementation calls {@link #defaultDestroy()}.
      * </p>
      * <p>
      * User still needs to destroy the upstream window, which details are hidden from this aspect.
+     * This can be performed by overriding {@link #destroyImplInLock()}. 
      * </p>
      */
     @Override
-    public void destroy() {
-        lock.lock();
-        try {
-            defaultDestroyOp();
-        } finally {
-            lock.unlock();
-        }
+    public final void destroy() {
+        defaultDestroy();
     }
 
     @Override
     public void display() {
-        if( sendDestroy ) {
-            sendDestroy=false;
-            destroy();
-            return;
-        }
-        
-        lock.lock(); // sync: context/drawable could been recreated/destroyed while animating
-        try {
-            if( null != drawable && drawable.isRealized() && null != context ) {
-                // surface is locked/unlocked implicit by context's makeCurrent/release
-                helper.invokeGL(drawable, context, defaultDisplayAction, defaultInitAction);
-            }
-        } finally {
-            lock.unlock();
-        }
+        defaultDisplay();
     }
     
     //
@@ -145,4 +130,9 @@ public class GLAutoDrawableDelegate extends GLAutoDrawableBase {
     public final void setRealized(boolean realized) {
     }
 
+    @Override
+    public final void swapBuffers() throws GLException {
+         defaultSwapBuffers();
+    }
+        
 }