Bug 983

(In reply to comment #0)
> He suggested the following workaround which worked in OpenJDK 1.7 update 45
> and Icedtea Webstart but didn't work in Windows with Oracle JVM:
> 
> if(AppContext.getAppContext() == null){ 
>     SunToolkit.createNewAppContext(); 
> } 
> 
Actually, OpenJDK supports your example as is without my workaround as it is NOT concerned by this bug.

(In reply to comment #1)
> Actually, OpenJDK supports your example as is without my workaround as it is
> NOT concerned by this bug.

This has been confirmed by 'runiter' as well, 
i.e. bug only affects Oracle's JRE/AWT.

Question now is whether we should and can provide a workaround
and why this only happens w/ Java3D.

I added Harvey to this bug (Java3D ..).

I changed the type to 'ANNOTATION', since it documents another bug.

Reduced to 'major' ..

At runiter, maybe you can go ahead and test certain remedies
and try a workaround ?

I couldn't find a workaround so far, but I'm going to try to remotely debug webstart+Java3D to see if I can find a cause or workaround that way. I'll keep you updated.

My debug result shows that in webstart mode, the value of AppContext.getAppContext() is indeed null at this line:

javax.media.j3d.JoglPipeline.createNewContext(JoglPipeline.java:6374)

Interestingly when JoglPipeline is created AppContext.getAppContext() is not null. But since JoglPipeline.createNewContext is called from javax.media.j3d.Renderer what matters is the context at the time of the creation of Renderer object.

My debug result shows that when Renderer is created, the value of AppContext.getAppContext() is indeed null. The cause of this can be traced back to javax.media.j3d.MasterControlThread which is in charge of creating Renderer. MasterControlThread has a non-null context at the time of its creation so I'm not sure why MasterControlThread.run() method ends up with a null context.

Thank you very much for debugging this, I know exactly why this happens, I believe MasterControl puts all the threads it manages in its own ThreadGroup, I won't have time to fix this before Saturday, but I'm pretty sure it's a trivial fix....THANK YOU very much for the analysis.

Glad I could be of help :) I will await your update hopefully in the weekend.

Hi Harvey, any updates on this? I noticed Java3D hasn't change in github yet.

diff --git a/src/classes/share/javax/media/j3d/JoglPipeline.java b/src/classes/share/javax/media/j3d/JoglPipeline.java
index 2d3c073..3f40b2c 100644
--- a/src/classes/share/javax/media/j3d/JoglPipeline.java
+++ b/src/classes/share/javax/media/j3d/JoglPipeline.java
@@ -36,6 +36,7 @@
 import java.awt.GraphicsDevice;
 import java.awt.GraphicsEnvironment;
 import java.io.UnsupportedEncodingException;
+import java.lang.reflect.Field;
 import java.lang.reflect.Method;
 import java.nio.Buffer;
 import java.nio.ByteBuffer;
@@ -46,6 +47,7 @@
 import java.security.PrivilegedAction;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Map;
 import java.util.StringTokenizer;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
@@ -99,10 +101,20 @@
     private static final int MIN_FRAME_SIZE = 1;
 
     private GLProfile profile;
+    
+    private Object mainThreadContext;	// Fix for Bug 983
+    
     /**
      * Constructor for singleton JoglPipeline instance
      */
     protected JoglPipeline() {
+    	// Fix for Bug 983
+		try {
+			// Retrieve main thread AppContext instance by reflection
+			mainThreadContext = Class.forName("sun.awt.AppContext").getMethod("getAppContext").invoke(null);
+		} catch (final Throwable ex) {
+			// Let's consider app context is not necessary for the program
+		}    	
     }
 
     /**
@@ -6350,6 +6362,29 @@
 			surface.unlockSurface();
 		}
     }
+    
+    // Fix for Bug 983
+	private void checkAppContext() {
+		if (mainThreadContext != null) {
+			try {
+				// Check by reflection that sun.awt.AppContext.getAppContext() doesn't return null
+				// (required by ImageIO.write() and other JMF internal calls) to apply workaround proposed at
+				// http://stackoverflow.com/questions/17223304/appcontext-is-null-from-rmi-thread-with-java-7-update-25
+				final Class<?> appContextClass = Class.forName("sun.awt.AppContext");
+				if (appContextClass.getMethod("getAppContext").invoke(null) == null) {
+					final Field field = appContextClass.getDeclaredField("threadGroup2appContext");
+					field.setAccessible(true);
+					final Map threadGroup2appContext = (Map)field.get(null);
+					final ThreadGroup currentThreadGroup = Thread.currentThread().getThreadGroup();
+					threadGroup2appContext.put(currentThreadGroup, mainThreadContext);
+				}
+			} catch (final Throwable ex) {
+				// Let's consider app context is not necessary for the program
+			}
+			// Don't need mainThreadContext anymore
+			mainThreadContext = null;
+		}
+	}    
 
     // This is the native method for creating the underlying graphics context.
     @Override
@@ -6357,6 +6392,8 @@
             Context shareCtx, boolean isSharedCtx,
             boolean offScreen) {
         if (VERBOSE) System.err.println("JoglPipeline.createNewContext()");
+        
+        checkAppContext();
 
 	    GLDrawable	glDrawable 	= null;
 	    GLContext 	glContext	= null;

Please apply the above patch which fixes this issue.

Also, it is possible that we no longer need the following commit:

https://github.com/hharrison/java3d-utils/commit/14206478b7a5bf628b59094c92d5727291c7c2bf

The above commit fixed the issue for JCanvas only. I think my patch which replicates the code in the above commit may cover both JCanvas and Canvas3D but I didn't test for that so can't be sure.

Either way the problem report in this bug is resolved with my patch. I tested in my Windows machine. Other tests are welcomed.

Applied to j3dcore
commit: bdda2ac20bfef85271da764d1989ec3434d5c67a

Applied removal of the old JCanvas3D workaround in j3dutils
commit: 1f025a8787edec6e2ae1eab3a3fd0eb59319e3c4

(In reply to comment #10)
> Applied to j3dcore
> commit: bdda2ac20bfef85271da764d1989ec3434d5c67a
> 
> Applied removal of the old JCanvas3D workaround in j3dutils
> commit: 1f025a8787edec6e2ae1eab3a3fd0eb59319e3c4

Pls consider using workaround of Bug 1004 Comment 4, i.e.:
  jogl aa1c04ebee23d0803880d6d68ae73109c1a5c178,
  uses gluegen f39100b35d0833764f2220e487ea7ea05ed87352

This will be crucial especial in cases of multiple AppContext 
per ClassLoader .. see comment.

(In reply to comment #11)
> (In reply to comment #10)
> > Applied to j3dcore
> > commit: bdda2ac20bfef85271da764d1989ec3434d5c67a
> > 
> > Applied removal of the old JCanvas3D workaround in j3dutils
> > commit: 1f025a8787edec6e2ae1eab3a3fd0eb59319e3c4
> 
> Pls consider using workaround of Bug 1004 Comment 4, i.e.:
>   jogl aa1c04ebee23d0803880d6d68ae73109c1a5c178,
>   uses gluegen f39100b35d0833764f2220e487ea7ea05ed87352
> 
> This will be crucial especial in cases of multiple AppContext 
> per ClassLoader .. see comment.

That would be _excellent_, i.e. the image format auto-detection!

IMHO it would be nice to have a static method returning the type,
as well as an overloaded 'load' texture method.

Nice!

(In reply to comment #12)
> (In reply to comment #11)
> > (In reply to comment #10)
> > > Applied to j3dcore
> > > commit: bdda2ac20bfef85271da764d1989ec3434d5c67a
> > > 
> > > Applied removal of the old JCanvas3D workaround in j3dutils
> > > commit: 1f025a8787edec6e2ae1eab3a3fd0eb59319e3c4
> > 
> > Pls consider using workaround of Bug 1004 Comment 4, i.e.:
> >   jogl aa1c04ebee23d0803880d6d68ae73109c1a5c178,
> >   uses gluegen f39100b35d0833764f2220e487ea7ea05ed87352
> > 
> > This will be crucial especial in cases of multiple AppContext 
> > per ClassLoader .. see comment.
> 
> That would be _excellent_, i.e. the image format auto-detection!
> 
> IMHO it would be nice to have a static method returning the type,
> as well as an overloaded 'load' texture method.
> 
> Nice!

Are you sure that you comment the good bug report?

(In reply to comment #13)
> > 
> > That would be _excellent_, i.e. the image format auto-detection!
> > 
> > IMHO it would be nice to have a static method returning the type,
> > as well as an overloaded 'load' texture method.
> > 
> > Nice!
> 
> Are you sure that you comment the good bug report?

sorry for bug 982 .. pls dismiss