Enhance and generalize AWT Threading* implementation; Minor changes ..

Threading*:
  - add invoke(..) generalizing the Therading decision

GLCanvas:
  - remove 'manual' Threading decision, simply call Threading.invoke(..)
  - use anonymous Runnable instances
  - remove drawable lock, drawable is volatile instead

GLJPanel:
  - remove 'manual' Threading decision, simply call Threading.invoke(..)
  - use anonymous Runnable instances
  - DEBUG: Use getThreadName() prefix

GLContextImpl:
  - Remove GLWorkerThread idle command on makeCurrent(),
    no holding of context in worker thread while idle.
  - DEBUG: Use getThreadName() prefix

X11GLXContext:
  - DEBUG: Use getThreadName() prefix

TODO: Validate whether it's OK for GLCanvas and GLJPanel to set Threading.Mode.MT as the default mode!

4 files changed, 183 insertions, 256 deletions

diff --git a/src/jogl/classes/javax/media/opengl/GLContext.java b/src/jogl/classes/javax/media/opengl/GLContext.java
index 41dce0d3b..51adce70c 100644
--- a/src/jogl/classes/javax/media/opengl/GLContext.java
+++ b/src/jogl/classes/javax/media/opengl/GLContext.java
@@ -66,9 +66,9 @@ import jogamp.opengl.GLContextImpl;
     abstraction provides a stable object which clients can use to
     refer to a given context. */
 public abstract class GLContext {
-  public static final boolean DEBUG = Debug.debug("GLContext");
+  public static final boolean DEBUG = Debug.debug("GLContext");  
+  public static final boolean TRACE_SWITCH = DEBUG || Debug.isPropertyDefined("jogl.debug.GLContext.TraceSwitch", true);
   
-  public static final boolean TRACE_SWITCH = Debug.isPropertyDefined("jogl.debug.GLContext.TraceSwitch", true);       
   /** Reflects property jogl.debug.DebugGL. If true, the debug pipeline is enabled at context creation. */
   public final static boolean DEBUG_GL = Debug.isPropertyDefined("jogl.debug.DebugGL", true);
   /** Reflects property jogl.debug.TraceGL. If true, the trace pipeline is enabled at context creation. */
diff --git a/src/jogl/classes/javax/media/opengl/Threading.java b/src/jogl/classes/javax/media/opengl/Threading.java
index 4871c1dd7..4788f9cf6 100644
--- a/src/jogl/classes/javax/media/opengl/Threading.java
+++ b/src/jogl/classes/javax/media/opengl/Threading.java
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2003 Sun Microsystems, Inc. All Rights Reserved.
+ * Copyright (c) 2012 JogAmp Community. All rights reserved.
  * 
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
@@ -39,7 +40,7 @@
 
 package javax.media.opengl;
 
-import jogamp.opengl.*;
+import jogamp.opengl.ThreadingImpl;
 
 /** This API provides access to the threading model for the implementation of 
     the classes in this package.
@@ -133,21 +134,27 @@ public class Threading {
         once disabled, partly to discourage careless use of this
         method. This method should be called as early as possible in an
         application. */ 
-    public static void disableSingleThreading() {
+    public static final void disableSingleThreading() {
         ThreadingImpl.disableSingleThreading();
     }
 
     /** Indicates whether OpenGL work is being automatically forced to a
         single thread in this implementation. */
-    public static boolean isSingleThreaded() {
+    public static final boolean isSingleThreaded() {
         return ThreadingImpl.isSingleThreaded();
     }
 
+    /** Indicates whether the current thread is the designated toolkit thread,
+        if such semantics exists. */    
+    public static final boolean isToolkitThread() throws GLException {
+        return ThreadingImpl.isToolkitThread();
+    }
+    
     /** Indicates whether the current thread is the single thread on
         which this implementation of the javax.media.opengl APIs
         performs all of its OpenGL-related work. This method should only
         be called if the single-thread model is in effect. */
-    public static boolean isOpenGLThread() throws GLException {
+    public static final boolean isOpenGLThread() throws GLException {
         return ThreadingImpl.isOpenGLThread();
     }
 
@@ -159,8 +166,31 @@ public class Threading {
         thread (i.e., if <code>isOpenGLThread()</code> returns
         false). It is up to the end user to check to see whether the
         current thread is the OpenGL thread and either execute the
-        Runnable directly or perform the work inside it. */
-    public static void invokeOnOpenGLThread(Runnable r) throws GLException {
-        ThreadingImpl.invokeOnOpenGLThread(r);
+        Runnable directly or perform the work inside it. 
+     **/
+    public static final void invokeOnOpenGLThread(boolean wait, Runnable r) throws GLException {
+        ThreadingImpl.invokeOnOpenGLThread(wait, r);
+    }
+    
+    /**
+     * If {@link #isSingleThreaded()} <b>and</b> not {@link #isOpenGLThread()}
+     * <b>and</b> the <code>lock</code> is not being hold by this thread,
+     * invoke Runnable <code>r</code> on the OpenGL thread via {@link #invokeOnOpenGLThread(boolean, Runnable)}.
+     * <p>
+     * Otherwise invoke Runnable <code>r</code> on the current thread.
+     * </p>
+     * 
+     * @param wait set to true for waiting until Runnable <code>r</code> is finished, otherwise false. 
+     * @param r the Runnable to be executed
+     * @param lock optional lock object to be tested
+     * @throws GLException
+     */
+    public static final void invoke(boolean wait, Runnable r, Object lock) throws GLException {
+        if ( isSingleThreaded() && !isOpenGLThread() && 
+             ( null == lock || !Thread.holdsLock(lock) ) ) {
+            invokeOnOpenGLThread(wait, r);
+        } else {
+            r.run();
+        }
     }
 }
diff --git a/src/jogl/classes/javax/media/opengl/awt/GLCanvas.java b/src/jogl/classes/javax/media/opengl/awt/GLCanvas.java
index 10d478b85..ea191810e 100644
--- a/src/jogl/classes/javax/media/opengl/awt/GLCanvas.java
+++ b/src/jogl/classes/javax/media/opengl/awt/GLCanvas.java
@@ -91,13 +91,9 @@ import com.jogamp.nativewindow.awt.AWTWindowClosingProtocol;
 import com.jogamp.nativewindow.awt.JAWTWindow;
 import com.jogamp.opengl.JoglVersion;
 
-import com.jogamp.common.util.locks.LockFactory;
-import com.jogamp.common.util.locks.RecursiveLock;
-
 import jogamp.opengl.Debug;
 import jogamp.opengl.GLContextImpl;
 import jogamp.opengl.GLDrawableHelper;
-import jogamp.opengl.ThreadingImpl;
 
 // FIXME: Subclasses need to call resetGLFunctionAvailability() on their
 // context whenever the displayChanged() function is called on our
@@ -144,7 +140,7 @@ public class GLCanvas extends Canvas implements AWTGLAutoDrawable, WindowClosing
 
   private GLDrawableHelper drawableHelper = new GLDrawableHelper();
   private AWTGraphicsConfiguration awtConfig;
-  private GLDrawable drawable;
+  private volatile GLDrawable drawable;
   private GLContextImpl context;
   private boolean sendReshape = false;
   
@@ -377,24 +373,17 @@ public class GLCanvas extends Canvas implements AWTGLAutoDrawable, WindowClosing
   }
   
   public GLContext createContext(GLContext shareWith) {
-      drawableSync.lock();
-      try {
-        return (null != drawable) ? drawable.createContext(shareWith) : null;
-      } finally {
-        drawableSync.unlock();
-      }
+      return (null != drawable) ? drawable.createContext(shareWith) : null;
   }
 
   public void setRealized(boolean realized) {
   }
 
   public boolean isRealized() {
-      drawableSync.lock();
-      try {
-        return ( null != drawable ) ? drawable.isRealized() : false;
-      } finally {
-        drawableSync.unlock();
-      }
+     return ( null != drawable ) ? drawable.isRealized() : false;
+  }
+  protected final boolean isRealizedImpl() {
+      return ( null != drawable ) ? drawable.isRealized() : false;
   }
 
   public int getDefaultCloseOperation() {
@@ -412,66 +401,43 @@ public class GLCanvas extends Canvas implements AWTGLAutoDrawable, WindowClosing
         }
         return; // not yet available ..
     }
-    maybeDoSingleThreadedWorkaround(displayOnEventDispatchThreadAction,
-                                    displayAction);
+    Threading.invoke(true, displayOnEventDispatchThreadAction, getTreeLock());
 
     awtWindowClosingProtocol.addClosingListenerOneShot();
   }
 
   private void dispose(boolean regenerate) {
-    drawableSync.lock();
-    try {
-        final GLAnimatorControl animator =  getAnimator();
-        if(DEBUG) {
-            System.err.println(getThreadName()+": Info: dispose("+regenerate+") - START, hasContext " +
-                    (null!=context) + ", hasDrawable " + (null!=drawable)+", "+animator);
-            Thread.dumpStack();
+    final GLAnimatorControl animator =  getAnimator();
+    if(DEBUG) {
+        System.err.println(getThreadName()+": Info: dispose("+regenerate+") - START, hasContext " +
+                (null!=context) + ", hasDrawable " + (null!=drawable)+", "+animator);
+        Thread.dumpStack();
+    }
+
+    if(null!=context) {
+        boolean animatorPaused = false;
+        if(null!=animator) {
+            // can't remove us from animator for recreational addNotify()
+            animatorPaused = animator.pause();
         }
 
-        if(null!=context) {
-            boolean animatorPaused = false;
-            if(null!=animator) {
-                // can't remove us from animator for recreational addNotify()
-                animatorPaused = animator.pause();
-            }
+        disposeRegenerate=regenerate;
 
-            disposeRegenerate=regenerate;
-
-            if(context.isCreated()) {
-                if (Threading.isSingleThreaded() &&
-                    !Threading.isOpenGLThread()) {
-                  // Workaround for termination issues with applets --
-                  // sun.applet.AppletPanel should probably be performing the
-                  // remove() call on the EDT rather than on its own thread
-                  // Hint: User should run remove from EDT.
-                  if (ThreadingImpl.isAWTMode() &&
-                      Thread.holdsLock(getTreeLock())) {
-                    // The user really should not be invoking remove() from this
-                    // thread -- but since he/she is, we can not go over to the
-                    // EDT at this point. Try to destroy the context from here.
-                    drawableHelper.disposeGL(GLCanvas.this, drawable, context, postDisposeAction);
-                  } else {
-                    Threading.invokeOnOpenGLThread(disposeOnEventDispatchThreadAction);
-                  }
-                } else {
-                  drawableHelper.disposeGL(GLCanvas.this, drawable, context, postDisposeAction);
-                }
-            }
-
-            if(animatorPaused) {
-                animator.resume();
-            }
-        }
-        
-        if(!regenerate) {
-            disposeAbstractGraphicsDevice();
+        if(context.isCreated()) {
+            Threading.invoke(true, disposeOnEventDispatchThreadAction, getTreeLock());
         }
 
-        if(DEBUG) {
-            System.err.println(getThreadName()+": dispose("+regenerate+") - END, "+animator);
+        if(animatorPaused) {
+            animator.resume();
         }
-    } finally {
-        drawableSync.unlock();
+    }
+    
+    if(!regenerate) {
+        disposeAbstractGraphicsDevice();
+    }
+
+    if(DEBUG) {
+        System.err.println(getThreadName()+": dispose("+regenerate+") - END, "+animator);
     }
   }
 
@@ -516,8 +482,6 @@ public class GLCanvas extends Canvas implements AWTGLAutoDrawable, WindowClosing
     }
   }
 
-  RecursiveLock drawableSync = LockFactory.createRecursiveLock();
-
   /** Overridden to track when this component is added to a container.
       Subclasses which override this method must call
       super.addNotify() in their addNotify() method in order to
@@ -533,43 +497,38 @@ public class GLCanvas extends Canvas implements AWTGLAutoDrawable, WindowClosing
         Thread.dumpStack();
     }
 
-    drawableSync.lock();
-    try {
-        /**
-         * 'super.addNotify()' determines the GraphicsConfiguration,
-         * while calling this class's overriden 'getGraphicsConfiguration()' method
-         * after which it creates the native peer.
-         * Hence we have to set the 'awtConfig' before since it's GraphicsConfiguration
-         * is being used in getGraphicsConfiguration().
-         * This code order also allows recreation, ie re-adding the GLCanvas.
-         */
-        awtConfig = chooseGraphicsConfiguration(capsReqUser, capsReqUser, chooser, device);
-        if(null==awtConfig) {
-            throw new GLException("Error: NULL AWTGraphicsConfiguration");
-        }
+    /**
+     * 'super.addNotify()' determines the GraphicsConfiguration,
+     * while calling this class's overriden 'getGraphicsConfiguration()' method
+     * after which it creates the native peer.
+     * Hence we have to set the 'awtConfig' before since it's GraphicsConfiguration
+     * is being used in getGraphicsConfiguration().
+     * This code order also allows recreation, ie re-adding the GLCanvas.
+     */
+    awtConfig = chooseGraphicsConfiguration(capsReqUser, capsReqUser, chooser, device);
+    if(null==awtConfig) {
+        throw new GLException("Error: NULL AWTGraphicsConfiguration");
+    }
 
-        // before native peer is valid: X11
-        disableBackgroundErase();
+    // before native peer is valid: X11
+    disableBackgroundErase();
 
-        // issues getGraphicsConfiguration() and creates the native peer
-        super.addNotify();
+    // issues getGraphicsConfiguration() and creates the native peer
+    super.addNotify();
 
-        // after native peer is valid: Windows
-        disableBackgroundErase();
+    // after native peer is valid: Windows
+    disableBackgroundErase();
 
-        if (!Beans.isDesignTime()) {
-            createDrawableAndContext();
-        }
+    if (!Beans.isDesignTime()) {
+        createDrawableAndContext();
+    }
 
-        // init drawable by paint/display makes the init sequence more equal
-        // for all launch flavors (applet/javaws/..)
-        // validateGLDrawable();
+    // init drawable by paint/display makes the init sequence more equal
+    // for all launch flavors (applet/javaws/..)
+    // validateGLDrawable();
 
-        if(DEBUG) {
-            System.err.println(getThreadName()+": Info: addNotify - end: peer: "+getPeer());
-        }
-    } finally {
-       drawableSync.unlock();
+    if(DEBUG) {
+        System.err.println(getThreadName()+": Info: addNotify - end: peer: "+getPeer());
     }
   }
 
@@ -591,22 +550,17 @@ public class GLCanvas extends Canvas implements AWTGLAutoDrawable, WindowClosing
   private boolean validateGLDrawable() {
     boolean realized = false;
     if (!Beans.isDesignTime()) {
-        drawableSync.lock();
-        try {
-            if ( null != drawable ) {
-                realized = drawable.isRealized();
-                if ( !realized && 0 < drawable.getWidth() * drawable.getHeight() ) {
-                    drawable.setRealized(true);
-                    realized = true;
-                    sendReshape=true; // ensure a reshape is being send ..
-                    if(DEBUG) {
-                        System.err.println(getThreadName()+": Realized Drawable: "+drawable.toString());
-                        Thread.dumpStack();
-                    }
+        if ( null != drawable ) {
+            realized = drawable.isRealized();
+            if ( !realized && 0 < drawable.getWidth() * drawable.getHeight() ) {
+                drawable.setRealized(true);
+                realized = true;
+                sendReshape=true; // ensure a reshape is being send ..
+                if(DEBUG) {
+                    System.err.println(getThreadName()+": Realized Drawable: "+drawable.toString());
+                    Thread.dumpStack();
                 }
             }
-        } finally {
-           drawableSync.unlock();
         }
     }
     return realized;
@@ -633,7 +587,6 @@ public class GLCanvas extends Canvas implements AWTGLAutoDrawable, WindowClosing
     if (Beans.isDesignTime()) {
       super.removeNotify();
     } else {
-      drawableSync.lock();
       try {
         dispose(false);
       } finally {
@@ -641,7 +594,6 @@ public class GLCanvas extends Canvas implements AWTGLAutoDrawable, WindowClosing
         drawable=null;
         awtConfig=null;
         super.removeNotify();
-        drawableSync.unlock();
       }
     }
     if(DEBUG) {
@@ -740,7 +692,7 @@ public class GLCanvas extends Canvas implements AWTGLAutoDrawable, WindowClosing
   }
 
   public void swapBuffers() {
-    maybeDoSingleThreadedWorkaround(swapBuffersOnEventDispatchThreadAction, swapBuffersAction);
+    Threading.invoke(true, swapBuffersOnEventDispatchThreadAction, getTreeLock());
   }
 
   public void setContextCreationFlags(int flags) {
@@ -772,30 +724,15 @@ public class GLCanvas extends Canvas implements AWTGLAutoDrawable, WindowClosing
   }
 
   public NativeSurface getNativeSurface() {
-      drawableSync.lock();
-      try {
-        return (null != drawable) ? drawable.getNativeSurface() : null;
-      } finally {
-        drawableSync.unlock();
-      }
+    return (null != drawable) ? drawable.getNativeSurface() : null;
   }
 
   public long getHandle() {
-      drawableSync.lock();
-      try {
-        return (null != drawable) ? drawable.getHandle() : 0;
-      } finally {
-        drawableSync.unlock();
-      }
+    return (null != drawable) ? drawable.getHandle() : 0;
   }
 
   public GLDrawableFactory getFactory() {
-      drawableSync.lock();
-      try {
-        return (null != drawable) ? drawable.getFactory() : null;
-      } finally {
-        drawableSync.unlock();
-      }
+    return (null != drawable) ? drawable.getFactory() : null;
   }
 
   @Override
@@ -805,7 +742,6 @@ public class GLCanvas extends Canvas implements AWTGLAutoDrawable, WindowClosing
     
     return "AWT-GLCanvas[Realized "+isRealized()+
                           ",\n\t"+((null!=drawable)?drawable.getClass().getName():"null-drawable")+                         
-                          ",\n\tRealized "+isRealized()+
                           ",\n\tFactory   "+getFactory()+
                           ",\n\thandle    0x"+Long.toHexString(getHandle())+
                           ",\n\tDrawable size "+dw+"x"+dh+
@@ -818,17 +754,8 @@ public class GLCanvas extends Canvas implements AWTGLAutoDrawable, WindowClosing
   // Internals only below this point
   //
 
-  private void maybeDoSingleThreadedWorkaround(Runnable eventDispatchThreadAction,
-                                               Runnable invokeGLAction) {
-    if (Threading.isSingleThreaded() &&
-        !Threading.isOpenGLThread()) {
-      Threading.invokeOnOpenGLThread(eventDispatchThreadAction);
-    } else {
-      drawableHelper.invokeGL(drawable, context, invokeGLAction, initAction);
-    }
-  }
-
-  class PostDisposeAction implements Runnable {
+  private boolean disposeRegenerate;
+  private final Runnable postDisposeAction = new Runnable() {
     public void run() {
       context=null;
       if(null!=drawable) {
@@ -852,20 +779,15 @@ public class GLCanvas extends Canvas implements AWTGLAutoDrawable, WindowClosing
           validateGLDrawable(); // immediate attempt to recreate the drawable
       }
     }
-  }
-  private boolean disposeRegenerate;
-  private PostDisposeAction postDisposeAction = new PostDisposeAction();
+  }; 
 
-  private DisposeOnEventDispatchThreadAction disposeOnEventDispatchThreadAction =
-    new DisposeOnEventDispatchThreadAction();
-
-  class DisposeOnEventDispatchThreadAction implements Runnable {
+  private final Runnable disposeOnEventDispatchThreadAction = new Runnable() {
     public void run() {
       drawableHelper.disposeGL(GLCanvas.this, drawable, context, postDisposeAction);      
     }
-  }
+  };
 
-  class DisposeAbstractGraphicsDeviceAction implements Runnable {
+  private final Runnable disposeAbstractGraphicsDeviceAction = new Runnable() {
     public void run() {
       if(null != awtConfig) {
           final AbstractGraphicsConfiguration aconfig = awtConfig.getNativeGraphicsConfiguration();          
@@ -883,8 +805,7 @@ public class GLCanvas extends Canvas implements AWTGLAutoDrawable, WindowClosing
           awtConfig=null;
       }
     }
-  }
-  private DisposeAbstractGraphicsDeviceAction disposeAbstractGraphicsDeviceAction = new DisposeAbstractGraphicsDeviceAction();
+  };
 
   /**
    * Disposes the AbstractGraphicsDevice within EDT,
@@ -906,14 +827,13 @@ public class GLCanvas extends Canvas implements AWTGLAutoDrawable, WindowClosing
     }
   }
 
-  class InitAction implements Runnable {
+  private final Runnable initAction = new Runnable() {
     public void run() {
       drawableHelper.init(GLCanvas.this);
     }
-  }
-  private InitAction initAction = new InitAction();
+  };
   
-  class DisplayAction implements Runnable {
+  private final Runnable displayAction = new Runnable() {
     public void run() {
       if (sendReshape) {
         if(DEBUG) {
@@ -927,33 +847,28 @@ public class GLCanvas extends Canvas implements AWTGLAutoDrawable, WindowClosing
 
       drawableHelper.display(GLCanvas.this);
     }
-  }
-  private DisplayAction displayAction = new DisplayAction();
+  };
 
-  class SwapBuffersAction implements Runnable {
+  private final Runnable swapBuffersAction = new Runnable() {
     public void run() {
       drawable.swapBuffers();
     }
-  }
-  private SwapBuffersAction swapBuffersAction = new SwapBuffersAction();
+  };
 
   // Workaround for ATI driver bugs related to multithreading issues
   // like simultaneous rendering via Animators to canvases that are
   // being resized on the AWT event dispatch thread
-  class DisplayOnEventDispatchThreadAction implements Runnable {
+  private final Runnable displayOnEventDispatchThreadAction = new Runnable() {
     public void run() {
-      drawableHelper.invokeGL(drawable, context, displayAction, initAction);
+        drawableHelper.invokeGL(drawable, context, displayAction, initAction);
     }
-  }
-  private DisplayOnEventDispatchThreadAction displayOnEventDispatchThreadAction =
-    new DisplayOnEventDispatchThreadAction();
-  class SwapBuffersOnEventDispatchThreadAction implements Runnable {
+  };
+  
+  private final Runnable swapBuffersOnEventDispatchThreadAction = new Runnable() {
     public void run() {
-      drawableHelper.invokeGL(drawable, context, swapBuffersAction, initAction);
-    }
-  }
-  private SwapBuffersOnEventDispatchThreadAction swapBuffersOnEventDispatchThreadAction =
-    new SwapBuffersOnEventDispatchThreadAction();
+        drawableHelper.invokeGL(drawable, context, swapBuffersAction, initAction);
+    }  
+  };
 
   // Disables the AWT's erasing of this Canvas's background on Windows
   // in Java SE 6. This internal API is not available in previous
diff --git a/src/jogl/classes/javax/media/opengl/awt/GLJPanel.java b/src/jogl/classes/javax/media/opengl/awt/GLJPanel.java
index 5291e48e4..5ca81a4b9 100644
--- a/src/jogl/classes/javax/media/opengl/awt/GLJPanel.java
+++ b/src/jogl/classes/javax/media/opengl/awt/GLJPanel.java
@@ -89,7 +89,6 @@ import jogamp.opengl.GLContextImpl;
 import jogamp.opengl.GLDrawableFactoryImpl;
 import jogamp.opengl.GLDrawableHelper;
 import jogamp.opengl.GLDrawableImpl;
-import jogamp.opengl.ThreadingImpl;
 import jogamp.opengl.awt.Java2D;
 import jogamp.opengl.awt.Java2DGLContext;
 
@@ -269,7 +268,7 @@ public class GLJPanel extends JPanel implements AWTGLAutoDrawable, WindowClosing
 
   protected void dispose() {
     if(DEBUG) {
-        System.err.println("Info: dispose() - start - "+Thread.currentThread().getName());
+        System.err.println(getThreadName()+": GLJPanel.dispose() - start");
         // Thread.dumpStack();
     }
 
@@ -281,23 +280,7 @@ public class GLJPanel extends JPanel implements AWTGLAutoDrawable, WindowClosing
       }
 
       if(backend.getContext().isCreated()) {      
-          if (Threading.isSingleThreaded() &&
-              !Threading.isOpenGLThread()) {
-              // Workaround for termination issues with applets --
-              // sun.applet.AppletPanel should probably be performing the
-              // remove() call on the EDT rather than on its own thread
-              if (ThreadingImpl.isAWTMode() &&
-                  Thread.holdsLock(getTreeLock())) {
-                // The user really should not be invoking remove() from this
-                // thread -- but since he/she is, we can not go over to the
-                // EDT at this point. Try to destroy the context from here.
-                drawableHelper.disposeGL(GLJPanel.this, backend.getDrawable(), backend.getContext(), postDisposeAction);
-              } else {
-                Threading.invokeOnOpenGLThread(disposeOnEventDispatchThreadAction);
-              }
-          } else {
-              drawableHelper.disposeGL(GLJPanel.this, backend.getDrawable(), backend.getContext(), postDisposeAction);
-          }
+          Threading.invoke(true, disposeAction, getTreeLock());
       }
       if(null != backend) {
           // not yet destroyed due to backend.isUsingOwnThreadManagment() == true
@@ -311,7 +294,7 @@ public class GLJPanel extends JPanel implements AWTGLAutoDrawable, WindowClosing
     }
     
     if(DEBUG) {
-        System.err.println("dispose() - stop");
+        System.err.println(getThreadName()+": GLJPanel.dispose() - stop");
     }
   }
 
@@ -368,9 +351,11 @@ public class GLJPanel extends JPanel implements AWTGLAutoDrawable, WindowClosing
     }
 
     updater.setGraphics(g);
+    
     backend.doPaintComponent(g);
   }
 
+  
   /** Overridden to track when this component is added to a container.
       Subclasses which override this method must call
       super.addNotify() in their addNotify() method in order to
@@ -381,7 +366,7 @@ public class GLJPanel extends JPanel implements AWTGLAutoDrawable, WindowClosing
   public void addNotify() {
     super.addNotify();
     if (DEBUG) {
-      System.err.println("GLJPanel.addNotify()");
+      System.err.println(getThreadName()+": GLJPanel.addNotify()");
     }
   }
 
@@ -624,7 +609,7 @@ public void reshape(int x, int y, int width, int height) {
     panelHeight = reshapeHeight;
 
     if (DEBUG) {
-      System.err.println("GLJPanel.handleReshape: (w,h) = (" +
+      System.err.println(getThreadName()+": GLJPanel.handleReshape: (w,h) = (" +
                          panelWidth + "," + panelHeight + ")");
     }
 
@@ -632,7 +617,7 @@ public void reshape(int x, int y, int width, int height) {
     backend.handleReshape();
     handleReshape = false;
   }
-
+  
   // This is used as the GLEventListener for the pbuffer-based backend
   // as well as the callback mechanism for the other backends
   class Updater implements GLEventListener {
@@ -660,7 +645,7 @@ public void reshape(int x, int y, int width, int height) {
       }
       if (sendReshape) {
         if (DEBUG) {
-          System.err.println("display: reshape(" + viewportX + "," + viewportY + " " + panelWidth + "x" + panelHeight + ")");
+          System.err.println(getThreadName()+": GLJPanel.display: reshape(" + viewportX + "," + viewportY + " " + panelWidth + "x" + panelHeight + ")");
         }
         drawableHelper.reshape(GLJPanel.this, viewportX, viewportY, panelWidth, panelHeight);
         sendReshape = false;
@@ -682,7 +667,7 @@ public void reshape(int x, int y, int width, int height) {
     return "AWT-GLJPanel[ "+((null!=backend)?backend.getDrawable().getClass().getName():"null-drawable")+"]";
   }
 
-  class PostDisposeAction implements Runnable {
+  private final Runnable postDisposeAction = new Runnable() {
       public void run() {
           if (backend != null && !backend.isUsingOwnThreadManagment()) {
               backend.destroy();
@@ -690,38 +675,31 @@ public void reshape(int x, int y, int width, int height) {
               isInitialized = false;      
           }
       }
-  }
-  private PostDisposeAction postDisposeAction = new PostDisposeAction();
-
-  private DisposeOnEventDispatchThreadAction disposeOnEventDispatchThreadAction =
-    new DisposeOnEventDispatchThreadAction();
+  }; 
 
-  class DisposeOnEventDispatchThreadAction implements Runnable {
+  private final Runnable disposeAction = new Runnable() {
     public void run() {
       drawableHelper.disposeGL(GLJPanel.this, backend.getDrawable(), backend.getContext(), postDisposeAction);
     }
-  }
-  
-  class InitAction implements Runnable {
+  }; 
+
+  private final Runnable updaterInitAction = new Runnable() {
     public void run() {
       updater.init(GLJPanel.this);
     }
-  }
-  private InitAction initAction = new InitAction();
+  };
 
-  class DisplayAction implements Runnable {
+  private final Runnable updaterDisplayAction = new Runnable() {
     public void run() {
       updater.display(GLJPanel.this);
     }
-  }
-  private DisplayAction displayAction = new DisplayAction();
+  };
 
-  class PaintImmediatelyAction implements Runnable {
+  private final Runnable paintImmediatelyAction = new Runnable() {
     public void run() {
       paintImmediately(0, 0, getWidth(), getHeight());
     }
-  }
-  private PaintImmediatelyAction paintImmediatelyAction = new PaintImmediatelyAction();
+  }; 
 
   private int getNextPowerOf2(int number) {
     // Workaround for problems where 0 width or height are transiently
@@ -738,6 +716,10 @@ public void reshape(int x, int y, int width, int height) {
     return tmp[0];
   }
 
+  protected static String getThreadName() {
+    return Thread.currentThread().getName();
+  }
+    
   //----------------------------------------------------------------------
   // Implementations of the various backends
   //
@@ -980,7 +962,7 @@ public void reshape(int x, int y, int width, int height) {
     
     public void initialize() {
       if(DEBUG) {
-          System.err.println("SoftwareBackend: initialize() - "+Thread.currentThread().getName());
+          System.err.println(getThreadName()+": SoftwareBackend: initialize()");
       }
       // Fall-through path: create an offscreen context instead
       offscreenDrawable = (GLDrawableImpl) factory.createOffscreenDrawable(
@@ -999,7 +981,7 @@ public void reshape(int x, int y, int width, int height) {
 
     public void destroy() {
       if(DEBUG) {
-          System.err.println("SoftwareBackend: destroy() - offscreenContext: "+(null!=offscreenContext)+" - offscreenDrawable: "+(null!=offscreenDrawable)+" - "+Thread.currentThread().getName());
+          System.err.println(getThreadName()+": SoftwareBackend: destroy() - offscreenContext: "+(null!=offscreenContext)+" - offscreenDrawable: "+(null!=offscreenDrawable));
       }
       if (offscreenContext != null) {
         offscreenContext.destroy();
@@ -1058,7 +1040,7 @@ public void reshape(int x, int y, int width, int height) {
     }
 
     protected void doPaintComponentImpl() {
-      drawableHelper.invokeGL(offscreenDrawable, offscreenContext, displayAction, initAction);
+      drawableHelper.invokeGL(offscreenDrawable, offscreenContext, updaterDisplayAction, updaterInitAction);
     }
 
     protected int getGLPixelType() {
@@ -1082,7 +1064,7 @@ public void reshape(int x, int y, int width, int height) {
         throw new InternalError("Creating pbuffer twice without destroying it (memory leak / correctness bug)");
       }
       if(DEBUG) {
-          System.err.println("PbufferBackend: initialize() - "+Thread.currentThread().getName());
+          System.err.println(getThreadName()+": PbufferBackend: initialize()");
       }
       try {
         pbuffer = factory.createGLPbuffer(null /* default platform device */,
@@ -1097,7 +1079,7 @@ public void reshape(int x, int y, int width, int height) {
       } catch (GLException e) {
         if (DEBUG) {
           e.printStackTrace();
-          System.err.println("Info: GLJPanel: Falling back on software rendering because of problems creating pbuffer");
+          System.err.println(getThreadName()+": GLJPanel: Falling back on software rendering because of problems creating pbuffer");
         }
         hardwareAccelerationDisabled = true;
         backend = null;
@@ -1108,7 +1090,7 @@ public void reshape(int x, int y, int width, int height) {
 
     public void destroy() {
       if(DEBUG) {
-          System.err.println("PbufferBackend: destroy() - pbuffer: "+(null!=pbuffer)+" - "+Thread.currentThread().getName());
+          System.err.println(getThreadName()+": PbufferBackend: destroy() - pbuffer: "+(null!=pbuffer));
       }
       if (pbuffer != null) {
         pbuffer.destroy();
@@ -1159,7 +1141,7 @@ public void reshape(int x, int y, int width, int height) {
       if ((panelWidth > pbufferWidth)                  || (panelHeight > pbufferHeight) ||
           (panelWidth < (pbufferWidth / shrinkFactor)) || (panelHeight < (pbufferHeight / shrinkFactor))) {
         if (DEBUG) {
-          System.err.println("Resizing pbuffer from (" + pbufferWidth + ", " + pbufferHeight + ") " +
+          System.err.println(getThreadName()+": Resizing pbuffer from (" + pbufferWidth + ", " + pbufferHeight + ") " +
                              " to fit (" + panelWidth + ", " + panelHeight + ")");
         }
         // Must destroy and recreate pbuffer to fit
@@ -1177,7 +1159,7 @@ public void reshape(int x, int y, int width, int height) {
             readBackWidthInPixels  = Math.max(1, panelWidth);
             readBackHeightInPixels = Math.max(1, panelHeight);
             if (DEBUG) {
-              System.err.println("Warning: falling back to software rendering due to bugs in OpenGL drivers");
+              System.err.println(getThreadName()+": Warning: falling back to software rendering due to bugs in OpenGL drivers");
               e.printStackTrace();
             }
             createAndInitializeBackend();
@@ -1189,7 +1171,7 @@ public void reshape(int x, int y, int width, int height) {
         pbufferWidth = getNextPowerOf2(panelWidth);
         pbufferHeight = getNextPowerOf2(panelHeight);
         if (DEBUG && !hardwareAccelerationDisabled) {
-          System.err.println("New pbuffer size is (" + pbufferWidth + ", " + pbufferHeight + ")");
+          System.err.println(getThreadName()+": New pbuffer size is (" + pbufferWidth + ", " + pbufferHeight + ")");
         }
         initialize();
       }
@@ -1277,7 +1259,7 @@ public void reshape(int x, int y, int width, int height) {
     
     public void initialize() {
       if(DEBUG) {
-          System.err.println("J2DOGL: initialize() - "+Thread.currentThread().getName());
+          System.err.println(getThreadName()+": J2DOGL: initialize()");
       }
       // No-op in this implementation; everything is done lazily
       isInitialized = true;
@@ -1287,7 +1269,7 @@ public void reshape(int x, int y, int width, int height) {
       Java2D.invokeWithOGLContextCurrent(null, new Runnable() {
           public void run() {
             if(DEBUG) {
-                System.err.println("J2DOGL: destroy() - joglContext: "+(null!=joglContext)+" - joglDrawable: "+(null!=joglDrawable)+" - "+Thread.currentThread().getName());
+                System.err.println(getThreadName()+": J2DOGL: destroy() - joglContext: "+(null!=joglContext)+" - joglDrawable: "+(null!=joglDrawable));
             }
             if (joglContext != null) {
               joglContext.destroy();
@@ -1347,12 +1329,12 @@ public void reshape(int x, int y, int width, int height) {
 
       if (r == null) {
         if (DEBUG) {
-          System.err.println("Java2D.getOGLScissorBox() returned null");
+          System.err.println(getThreadName()+": Java2D.getOGLScissorBox() returned null");
         }
         return false;
       }
       if (DEBUG) {
-        System.err.println("GLJPanel: gl.glScissor(" + r.x + ", " + r.y + ", " + r.width + ", " + r.height + ")");
+        System.err.println(getThreadName()+": GLJPanel: gl.glScissor(" + r.x + ", " + r.y + ", " + r.width + ", " + r.height + ")");
       }
 
       gl.glScissor(r.x, r.y, r.width, r.height);
@@ -1364,7 +1346,7 @@ public void reshape(int x, int y, int width, int height) {
           (viewportY != oglViewport.y)) {
         sendReshape = true;
         if (DEBUG) {
-          System.err.println("Sending reshape because viewport changed");
+          System.err.println(getThreadName()+": Sending reshape because viewport changed");
           System.err.println("  viewportX (" + viewportX + ") ?= oglViewport.x (" + oglViewport.x + ")");
           System.err.println("  viewportY (" + viewportY + ") ?= oglViewport.y (" + oglViewport.y + ")");
         }
@@ -1393,14 +1375,14 @@ public void reshape(int x, int y, int width, int height) {
               fbObjectWorkarounds = true;
               createNewDepthBuffer = true;
               if (DEBUG) {
-                  System.err.println("GLJPanel: ERR GL_FRAMEBUFFER_BINDING: Discovered Invalid J2D FBO("+frameBuffer[0]+"): "+FBObject.getStatusString(status) +
+                  System.err.println(getThreadName()+": GLJPanel: ERR GL_FRAMEBUFFER_BINDING: Discovered Invalid J2D FBO("+frameBuffer[0]+"): "+FBObject.getStatusString(status) +
                                      ", frame_buffer_object workarounds to be necessary");
               }
           } else {
             // Don't need the frameBufferTexture temporary any more
             frameBufferTexture = null;
             if (DEBUG) {
-              System.err.println("GLJPanel: OK GL_FRAMEBUFFER_BINDING: "+frameBuffer[0]);
+              System.err.println(getThreadName()+": GLJPanel: OK GL_FRAMEBUFFER_BINDING: "+frameBuffer[0]);
             }
           }
         }
@@ -1424,7 +1406,7 @@ public void reshape(int x, int y, int width, int height) {
                     
           gl.glGenRenderbuffers(1, frameBufferDepthBuffer, 0);
           if (DEBUG) {
-            System.err.println("GLJPanel: Generated frameBufferDepthBuffer " + frameBufferDepthBuffer[0] +
+            System.err.println(getThreadName()+": GLJPanel: Generated frameBufferDepthBuffer " + frameBufferDepthBuffer[0] +
                                " with width " + width[0] + ", height " + height[0]);
           }
                     
@@ -1447,7 +1429,7 @@ public void reshape(int x, int y, int width, int height) {
                                     frameBufferTexture[0],
                                     0);
           if (DEBUG) {
-            System.err.println("GLJPanel: frameBufferDepthBuffer: " + frameBufferDepthBuffer[0]);
+            System.err.println(getThreadName()+": GLJPanel: frameBufferDepthBuffer: " + frameBufferDepthBuffer[0]);
           }
           gl.glFramebufferRenderbuffer(GL.GL_FRAMEBUFFER,
                                        GL.GL_DEPTH_ATTACHMENT,
@@ -1464,7 +1446,7 @@ public void reshape(int x, int y, int width, int height) {
         }
       } else {
         if (DEBUG) {
-          System.err.println("GLJPanel: Setting up drawBuffer " + drawBuffer[0] +
+          System.err.println(getThreadName()+": GLJPanel: Setting up drawBuffer " + drawBuffer[0] +
                              " and readBuffer " + readBuffer[0]);
         }
 
@@ -1522,14 +1504,14 @@ public void reshape(int x, int y, int width, int height) {
       Java2D.invokeWithOGLContextCurrent(g, new Runnable() {
           public void run() {
             if (DEBUG) {
-              System.err.println("-- In invokeWithOGLContextCurrent - "+Thread.currentThread().getName());
+              System.err.println(getThreadName()+": GLJPanel.invokeWithOGLContextCurrent");
             }
 
             // Create no-op context representing Java2D context
             if (j2dContext == null) {
               j2dContext = factory.createExternalGLContext();
               if (DEBUG) {
-                System.err.println("-- Created External Context: "+j2dContext);
+                System.err.println(getThreadName()+": GLJPanel.Created External Context: "+j2dContext);
               }
               if (DEBUG) {
 //                j2dContext.setGL(new DebugGL2(j2dContext.getGL().getGL2()));
@@ -1552,7 +1534,7 @@ public void reshape(int x, int y, int width, int height) {
                   //          (getGLInteger(gl, GL2.GL_DEPTH_BITS)       < offscreenCaps.getDepthBits())      ||
                   (getGLInteger(gl, GL.GL_STENCIL_BITS)     < offscreenCaps.getStencilBits())) {
                 if (DEBUG) {
-                  System.err.println("GLJPanel: Falling back to pbuffer-based support because Java2D context insufficient");
+                  System.err.println(getThreadName()+": GLJPanel: Falling back to pbuffer-based support because Java2D context insufficient");
                   System.err.println("                    Available              Required");
                   System.err.println("GL_RED_BITS         " + getGLInteger(gl, GL.GL_RED_BITS)         + "              " + offscreenCaps.getRedBits());
                   System.err.println("GL_GREEN_BITS       " + getGLInteger(gl, GL.GL_GREEN_BITS)       + "              " + offscreenCaps.getGreenBits());
@@ -1587,13 +1569,13 @@ public void reshape(int x, int y, int width, int height) {
                     joglDrawable = null;
                     sendReshape = true;
                     if (DEBUG) {
-                      System.err.println("Sending reshape because surface changed");
+                      System.err.println(getThreadName()+": Sending reshape because surface changed");
                       System.err.println("New surface = " + curSurface);
                     }
                   }
                   j2dSurface = curSurface;
                   if (DEBUG) {
-                      System.err.print("-- Surface type: ");
+                      System.err.print(getThreadName()+": Surface type: ");
                       int surfaceType = Java2D.getOGLSurfaceType(g);
                       if (surfaceType == Java2D.UNDEFINED) {
                         System.err.println("UNDEFINED");
@@ -1645,7 +1627,7 @@ public void reshape(int x, int y, int width, int height) {
                   ((Java2DGLContext) joglContext).setGraphics(g);
                 }
 
-                drawableHelper.invokeGL(joglDrawable, joglContext, displayAction, initAction);
+                drawableHelper.invokeGL(joglDrawable, joglContext, updaterDisplayAction, updaterInitAction);
               }
             } finally {
               j2dContext.release();
@@ -1665,11 +1647,11 @@ public void reshape(int x, int y, int width, int height) {
           fbObjectWorkarounds = true;
           createNewDepthBuffer = true;
           if (DEBUG) {
-              System.err.println("GLJPanel: Fetched ERR GL_FRAMEBUFFER_BINDING: "+frameBuffer[0]+" - NOT A FBO"+
+              System.err.println(getThreadName()+": GLJPanel: Fetched ERR GL_FRAMEBUFFER_BINDING: "+frameBuffer[0]+" - NOT A FBO"+
                                  ", frame_buffer_object workarounds to be necessary");
           }
         } else if (DEBUG) {
-          System.err.println("GLJPanel: Fetched OK GL_FRAMEBUFFER_BINDING: "+frameBuffer[0]);
+          System.err.println(getThreadName()+": GLJPanel: Fetched OK GL_FRAMEBUFFER_BINDING: "+frameBuffer[0]);
         }
 
         if(fbObjectWorkarounds || !checkedForFBObjectWorkarounds) {
@@ -1684,7 +1666,7 @@ public void reshape(int x, int y, int width, int height) {
                                                      GL.GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME,
                                                      frameBufferTexture, 0);
             if (DEBUG) {
-                System.err.println("GLJPanel: FBO COLOR_ATTACHMENT0: " + frameBufferTexture[0]);
+                System.err.println(getThreadName()+": GLJPanel: FBO COLOR_ATTACHMENT0: " + frameBufferTexture[0]);
             }
         }