Workaround MacOS + SWT 4.26: java.lang.NullPointerException: Cannot invoke "org.eclipse.swt.internal.cocoa.NSGraphicsContext.saveGraphicsState()" because "context" is null

On MacOS 12+ and SWT 4.26 while not using AWT (-Djava.awt.headless=true, -XstartOnFirstThread),
we recently get the following Exception from SWT (suppressed):

java.lang.NullPointerException: Cannot invoke "org.eclipse.swt.internal.cocoa.NSGraphicsContext.saveGraphicsState()" because "context" is null
        at org.eclipse.swt.widgets.Widget.drawRect(Widget.java:764)
        at org.eclipse.swt.widgets.Canvas.drawRect(Canvas.java:170)
        at org.eclipse.swt.widgets.Display.windowProc(Display.java:6287)
        at org.eclipse.swt.internal.cocoa.OS.objc_msgSendSuper(Native Method)
        at org.eclipse.swt.widgets.Display.applicationNextEventMatchingMask(Display.java:5565)
        at org.eclipse.swt.widgets.Display.applicationProc(Display.java:5965)
        at org.eclipse.swt.internal.cocoa.OS.objc_msgSend(Native Method)
        at org.eclipse.swt.internal.cocoa.NSApplication.nextEventMatchingMask(NSApplication.java:92)
        at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3983)
        at com.jogamp.opengl.test.junit.util.SWTTestUtil$WaitAction$1.run(SWTTestUtil.java:52)
        at org.eclipse.swt.widgets.Synchronizer.syncExec(Synchronizer.java:183)
        at org.eclipse.swt.widgets.Display.syncExec(Display.java:5250)
        at com.jogamp.opengl.test.junit.util.SWTTestUtil$WaitAction.run(SWTTestUtil.java:63)
        at com.jogamp.opengl.test.junit.jogl.acore.TestSharedContextVBOES2SWT3.test02AsyncEachAnimator(TestSharedContextVBOES2SWT3.java:376)

This is not observed if running using AWT (-Djava.awt.headless=false).

4 files changed, 143 insertions, 67 deletions

diff --git a/src/test/com/jogamp/opengl/test/junit/jogl/acore/TestSharedContextVBOES2SWT3.java b/src/test/com/jogamp/opengl/test/junit/jogl/acore/TestSharedContextVBOES2SWT3.java
index ba1486010..47e0c579a 100644
--- a/src/test/com/jogamp/opengl/test/junit/jogl/acore/TestSharedContextVBOES2SWT3.java
+++ b/src/test/com/jogamp/opengl/test/junit/jogl/acore/TestSharedContextVBOES2SWT3.java
@@ -72,6 +72,28 @@ import org.junit.runners.MethodSorters;
  * to initialize all in order, since otherwise the <i>test main thread</i>
  * itself blocks SWT GLCanvas creation ..
  * </p>
+ * <p>
+ * On MacOS 12+ and SWT 4.26 while not using AWT (-Djava.awt.headless=true, -XstartOnFirstThread),
+ * we recently get the following Exception from SWT (suppressed):
+ * <pre>
+java.lang.NullPointerException: Cannot invoke "org.eclipse.swt.internal.cocoa.NSGraphicsContext.saveGraphicsState()" because "context" is null
+        at org.eclipse.swt.widgets.Widget.drawRect(Widget.java:764)
+        at org.eclipse.swt.widgets.Canvas.drawRect(Canvas.java:170)
+        at org.eclipse.swt.widgets.Display.windowProc(Display.java:6287)
+        at org.eclipse.swt.internal.cocoa.OS.objc_msgSendSuper(Native Method)
+        at org.eclipse.swt.widgets.Display.applicationNextEventMatchingMask(Display.java:5565)
+        at org.eclipse.swt.widgets.Display.applicationProc(Display.java:5965)
+        at org.eclipse.swt.internal.cocoa.OS.objc_msgSend(Native Method)
+        at org.eclipse.swt.internal.cocoa.NSApplication.nextEventMatchingMask(NSApplication.java:92)
+        at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3983)
+        at com.jogamp.opengl.test.junit.util.SWTTestUtil$WaitAction$1.run(SWTTestUtil.java:52)
+        at org.eclipse.swt.widgets.Synchronizer.syncExec(Synchronizer.java:183)
+        at org.eclipse.swt.widgets.Display.syncExec(Display.java:5250)
+        at com.jogamp.opengl.test.junit.util.SWTTestUtil$WaitAction.run(SWTTestUtil.java:63)
+        at com.jogamp.opengl.test.junit.jogl.acore.TestSharedContextVBOES2SWT3.test02AsyncEachAnimator(TestSharedContextVBOES2SWT3.java:376)
+ * </pre>
+ * This is not observed if running using AWT (-Djava.awt.headless=false).
+ * </p>
  */
 @FixMethodOrder(MethodSorters.NAME_ASCENDING)
 public class TestSharedContextVBOES2SWT3 extends UITestCase {
@@ -104,11 +126,13 @@ public class TestSharedContextVBOES2SWT3 extends UITestCase {
     @Before
     public void init() {
         SWTAccessor.invokeOnOSTKThread(true, new Runnable() {
+            @Override
             public void run() {
                 display = new Display();
                 Assert.assertNotNull( display );
             }});
         display.syncExec(new Runnable() {
+            @Override
             public void run() {
                 shell1 = new Shell( display );
                 shell1.setLayout( new FillLayout() );
@@ -138,18 +162,20 @@ public class TestSharedContextVBOES2SWT3 extends UITestCase {
         Assert.assertNotNull( composite3 );
         try {
             display.syncExec(new Runnable() {
-               public void run() {
-                composite3.dispose();
-                shell3.dispose();
-                composite2.dispose();
-                shell2.dispose();
-                composite1.dispose();
-                shell1.dispose();
-               }});
+                @Override
+                public void run() {
+                    composite3.dispose();
+                    shell3.dispose();
+                    composite2.dispose();
+                    shell2.dispose();
+                    composite1.dispose();
+                    shell1.dispose();
+                }});
             SWTAccessor.invokeOnOSTKThread(true, new Runnable() {
-               public void run() {
-                display.dispose();
-               }});
+                @Override
+                public void run() {
+                    display.dispose();
+                }});
         }
         catch( final Throwable throwable ) {
             throwable.printStackTrace();
@@ -169,11 +195,12 @@ public class TestSharedContextVBOES2SWT3 extends UITestCase {
         Assert.assertNotNull( glCanvas );
         glCanvas.addGLEventListener(gears);
         display.syncExec(new Runnable() {
-           public void run() {
-            shell.setText("SWT GLCanvas Shared Gears Test");
-            shell.setSize( width, height);
-            shell.setLocation(x, y);
-           } } );
+            @Override
+            public void run() {
+                shell.setText("SWT GLCanvas Shared Gears Test");
+                shell.setSize( width, height);
+                shell.setLocation(x, y);
+            } } );
         return glCanvas;
     }
 
@@ -199,11 +226,12 @@ public class TestSharedContextVBOES2SWT3 extends UITestCase {
         animator.add(c3);
 
         display.syncExec(new Runnable() {
-           public void run() {
-            shell1.open();  // master ..
-            shell2.open();  // shall wait until f1 is ready
-            shell3.open();  // shall wait until f1 is ready
-           } } );
+            @Override
+            public void run() {
+                shell1.open();  // master ..
+                shell2.open();  // shall wait until f1 is ready
+                shell3.open();  // shall wait until f1 is ready
+            } } );
         final long t0 = System.currentTimeMillis();
         animator.start(); // kicks off GLContext .. and hence gears of f2 + f3 completion
 
@@ -253,11 +281,12 @@ public class TestSharedContextVBOES2SWT3 extends UITestCase {
         Assert.assertEquals(false, animator.isAnimating());
 
         display.syncExec(new Runnable() {
-           public void run() {
-            c3.dispose();
-            c2.dispose();
-            c1.dispose();
-           } } );
+            @Override
+            public void run() {
+                c3.dispose();
+                c2.dispose();
+                c1.dispose();
+            } } );
     }
 
     @Test
@@ -267,19 +296,25 @@ public class TestSharedContextVBOES2SWT3 extends UITestCase {
         g1.setSyncObjects(g1); // this is master, since rendered we must use it as sync
         // g1.setUseMappedBuffers(useMappedBuffers);
         g1.setValidateBuffers(true);
+        System.err.println("TestSharedContextVBOES2SWT3.test02AsyncEachAnimator: 0.0");
         final GLCanvas c1 = createGLCanvas(shell1, composite1, 0, 0, g1);
         a1.add(c1);
         display.syncExec(new Runnable() {
-           public void run() {
-            shell1.open();
-           } } );
+            @Override
+            public void run() {
+                shell1.open();
+            } } );
         a1.start();
 
+        System.err.println("TestSharedContextVBOES2SWT3.test02AsyncEachAnimator: 1.0");
         final SWTTestUtil.WaitAction waitAction = new SWTTestUtil.WaitAction(display, true, 200);
         Assert.assertEquals(true,  GLTestUtil.waitForRealized(c1, true, waitAction));
+        System.err.println("TestSharedContextVBOES2SWT3.test02AsyncEachAnimator: 1.1");
         Assert.assertEquals(true,  GLTestUtil.waitForContextCreated(c1, true, waitAction));
+        System.err.println("TestSharedContextVBOES2SWT3.test02AsyncEachAnimator: 1.2");
         Assert.assertTrue("Gears1 not initialized", g1.waitForInit(true));
 
+        System.err.println("TestSharedContextVBOES2SWT3.test02AsyncEachAnimator: 2.0");
         final Animator a2 = new Animator();
         final GearsES2 g2 = new GearsES2(0);
         g2.setSharedGears(g1);
@@ -287,11 +322,13 @@ public class TestSharedContextVBOES2SWT3 extends UITestCase {
         c2.setSharedAutoDrawable(c1);
         a2.add(c2);
         display.syncExec(new Runnable() {
-           public void run() {
-            shell2.open();
-           } } );
+            @Override
+            public void run() {
+                shell2.open();
+            } } );
         a2.start();
 
+        System.err.println("TestSharedContextVBOES2SWT3.test02AsyncEachAnimator: 3.0");
         final Animator a3 = new Animator();
         final GearsES2 g3 = new GearsES2(0);
         g3.setSharedGears(g1);
@@ -299,19 +336,27 @@ public class TestSharedContextVBOES2SWT3 extends UITestCase {
         c3.setSharedAutoDrawable(c1);
         a3.add(c3);
         display.syncExec(new Runnable() {
-           public void run() {
-            shell3.open();
-           } } );
+            @Override
+            public void run() {
+                shell3.open();
+            } } );
         a3.start();
 
+        System.err.println("TestSharedContextVBOES2SWT3.test02AsyncEachAnimator: 4.0");
         Assert.assertEquals(true,  GLTestUtil.waitForRealized(c2, true, waitAction));
+        System.err.println("TestSharedContextVBOES2SWT3.test02AsyncEachAnimator: 4.1: Exception "+(null != waitAction.getException(true)));
         Assert.assertEquals(true,  GLTestUtil.waitForContextCreated(c2, true, waitAction));
+        System.err.println("TestSharedContextVBOES2SWT3.test02AsyncEachAnimator: 4.2: Exception "+(null != waitAction.getException(true)));
         Assert.assertTrue("Gears2 not initialized", g2.waitForInit(true));
 
+        System.err.println("TestSharedContextVBOES2SWT3.test02AsyncEachAnimator: 5.0: Exception "+(null != waitAction.getException(true)));
         Assert.assertEquals(true,  GLTestUtil.waitForRealized(c3, true, waitAction));
+        System.err.println("TestSharedContextVBOES2SWT3.test02AsyncEachAnimator: 5.1: Exception "+(null != waitAction.getException(true)));
         Assert.assertEquals(true,  GLTestUtil.waitForContextCreated(c3, true, waitAction));
+        System.err.println("TestSharedContextVBOES2SWT3.test02AsyncEachAnimator: 5.2: Exception "+(null != waitAction.getException(true)));
         Assert.assertTrue("Gears3 not initialized", g3.waitForInit(true));
 
+        System.err.println("TestSharedContextVBOES2SWT3.test02AsyncEachAnimator: 6.0: Exception "+(null != waitAction.getException(true)));
         final long t0 = System.currentTimeMillis();
 
         final GLContext ctx1 = c1.getContext();
@@ -340,6 +385,7 @@ public class TestSharedContextVBOES2SWT3 extends UITestCase {
         while(System.currentTimeMillis()-t0<duration) {
             waitAction.run();
         }
+        System.err.println("TestSharedContextVBOES2SWT3.test02AsyncEachAnimator: 8.0: Exception "+(null != waitAction.getException(true)));
         // Stopped animator allows native windowing system 'repaint' event
         // to trigger GLAD 'display'
         a1.stop();
@@ -350,14 +396,15 @@ public class TestSharedContextVBOES2SWT3 extends UITestCase {
         Assert.assertEquals(false, a3.isAnimating());
 
         display.syncExec(new Runnable() {
-           public void run() {
-            c3.dispose();
-            c2.dispose();
-            c1.dispose();
-           } } );
+            @Override
+            public void run() {
+                c3.dispose();
+                c2.dispose();
+                c1.dispose();
+            } } );
     }
 
-    static long duration = 1000; // ms
+    static long duration = 2000; // ms
 
     public static void main(final String args[]) {
         for(int i=0; i<args.length; i++) {
diff --git a/src/test/com/jogamp/opengl/test/junit/jogl/demos/es2/swt/TestGearsES2SWT.java b/src/test/com/jogamp/opengl/test/junit/jogl/demos/es2/swt/TestGearsES2SWT.java
index 9ca6577b0..0b2d42bcf 100644
--- a/src/test/com/jogamp/opengl/test/junit/jogl/demos/es2/swt/TestGearsES2SWT.java
+++ b/src/test/com/jogamp/opengl/test/junit/jogl/demos/es2/swt/TestGearsES2SWT.java
@@ -102,11 +102,13 @@ public class TestGearsES2SWT extends UITestCase {
     @Before
     public void init() {
         SWTAccessor.invokeOnOSTKThread(true, new Runnable() {
+            @Override
             public void run() {
                 display = new Display();
                 Assert.assertNotNull( display );
             }});
         display.syncExec(new Runnable() {
+            @Override
             public void run() {
                 shell = new Shell( display );
                 Assert.assertNotNull( shell );
@@ -124,14 +126,16 @@ public class TestGearsES2SWT extends UITestCase {
         Assert.assertNotNull( composite );
         try {
             display.syncExec(new Runnable() {
-               public void run() {
-                composite.dispose();
-                shell.dispose();
-               }});
+                @Override
+                public void run() {
+                    composite.dispose();
+                    shell.dispose();
+                }});
             SWTAccessor.invokeOnOSTKThread(true, new Runnable() {
-               public void run() {
-                display.dispose();
-               }});
+                @Override
+                public void run() {
+                    display.dispose();
+                }});
         }
         catch( final Throwable throwable ) {
             throwable.printStackTrace();
@@ -162,28 +166,33 @@ public class TestGearsES2SWT extends UITestCase {
         Assert.assertEquals(exclusiveContext ? animator.getThread() : null, canvas.getExclusiveContextThread());
 
         display.syncExec( new Runnable() {
-           public void run() {
-              shell.setText( getSimpleTestName(".") );
-              shell.setSize( wsize.getWidth(), wsize.getHeight() );
-              if( null != wpos ) {
-                  shell.setLocation( wpos.getX(), wpos.getY() );
-              }
-              shell.open();
-           }
+            @Override
+            public void run() {
+                shell.setText( getSimpleTestName(".") );
+                shell.setSize( wsize.getWidth(), wsize.getHeight() );
+                if( null != wpos ) {
+                    shell.setLocation( wpos.getX(), wpos.getY() );
+                }
+                shell.open();
+            }
         });
 
         animator.setUpdateFPSFrames(60, showFPS ? System.err : null);
 
         final SWTTestUtil.WaitAction waitAction = new SWTTestUtil.WaitAction(display, true, 16);
 
+        System.err.println("TestGearsES2SWT.test: 2.0: Exception "+(null != waitAction.getException(true)));
         Assert.assertEquals(true,  GLTestUtil.waitForRealized(canvas, true, waitAction));
+        System.err.println("TestGearsES2SWT.test: 2.1: Exception "+(null != waitAction.getException(true)));
 
         while(animator.isAnimating() && !canvas.isRealized() && animator.getTotalFPSDuration()<duration) {
             waitAction.run();
         }
+        System.err.println("TestGearsES2SWT.test: 3.0: Exception "+(null != waitAction.getException(true)));
         System.err.println("NW chosen: "+canvas.getDelegatedDrawable().getChosenGLCapabilities());
         System.err.println("GL chosen: "+canvas.getChosenGLCapabilities());
         display.syncExec(new Runnable() {
+            @Override
             public void run() {
                 System.err.println("window pos/siz: "+canvas.getLocation()+" "+canvas.getSurfaceWidth()+"x"+canvas.getSurfaceHeight());
             } } );
@@ -192,10 +201,12 @@ public class TestGearsES2SWT extends UITestCase {
             for(int i=0; i<50; i++) { // 500 ms dispatched delay
                 waitAction.run();
             }
+            System.err.println("TestGearsES2SWT.test: 4.0: Exception "+(null != waitAction.getException(true)));
             display.syncExec( new Runnable() {
-               public void run() {
-                  shell.setSize( rwsize.getWidth(), rwsize.getHeight() );
-               }
+                @Override
+                public void run() {
+                    shell.setSize( rwsize.getWidth(), rwsize.getHeight() );
+                }
             });
             System.err.println("window resize pos/siz: "+canvas.getLocation()+" "+canvas.getSurfaceWidth()+"x"+canvas.getSurfaceHeight());
         }
@@ -203,6 +214,7 @@ public class TestGearsES2SWT extends UITestCase {
         while(animator.isAnimating() && animator.getTotalFPSDuration()<duration) {
             waitAction.run();
         }
+        System.err.println("TestGearsES2SWT.test: 5.0: Exception "+(null != waitAction.getException(true)));
 
         Assert.assertEquals(exclusiveContext ? animator.getThread() : null, canvas.getExclusiveContextThread());
         animator.stop();
@@ -211,9 +223,10 @@ public class TestGearsES2SWT extends UITestCase {
         Assert.assertEquals(null, canvas.getExclusiveContextThread());
 
         display.syncExec(new Runnable() {
-           public void run() {
-               canvas.dispose();
-           } } );
+            @Override
+            public void run() {
+                canvas.dispose();
+            } } );
     }
 
     @Test
diff --git a/src/test/com/jogamp/opengl/test/junit/util/GLTestUtil.java b/src/test/com/jogamp/opengl/test/junit/util/GLTestUtil.java
index 792dfa831..323cbb537 100644
--- a/src/test/com/jogamp/opengl/test/junit/util/GLTestUtil.java
+++ b/src/test/com/jogamp/opengl/test/junit/util/GLTestUtil.java
@@ -99,7 +99,10 @@ public class GLTestUtil extends TestUtil {
             }
             t1 = System.currentTimeMillis();
         }
-        return (t1-t0) < TIME_OUT;
+        final boolean to = (t1-t0) >= TIME_OUT;
+        final boolean ok = realized == glad.isRealized();
+        System.err.println("waitForRealized: to "+to+", goal reached "+ok);
+        return !to || ok;
     }
 
 }
diff --git a/src/test/com/jogamp/opengl/test/junit/util/SWTTestUtil.java b/src/test/com/jogamp/opengl/test/junit/util/SWTTestUtil.java
index 5e80bacaa..91e4d603d 100644
--- a/src/test/com/jogamp/opengl/test/junit/util/SWTTestUtil.java
+++ b/src/test/com/jogamp/opengl/test/junit/util/SWTTestUtil.java
@@ -38,6 +38,7 @@ public class SWTTestUtil {
         final Display display;
         final boolean blocking;
         final long sleepMS;
+        volatile Exception exo = null;
 
         public WaitAction(final Display display, final boolean blocking, final long sleepMS) {
             this.display = display;
@@ -57,12 +58,24 @@ public class SWTTestUtil {
 
         @Override
         public void run() {
-            if( blocking ) {
-                display.syncExec( waitAction0 );
-            } else {
-                display.asyncExec( waitAction0 );
+            try {
+                if( blocking ) {
+                    display.syncExec( waitAction0 );
+                } else {
+                    display.asyncExec( waitAction0 );
+                }
+            } catch (final Exception ex) {
+                ex.printStackTrace();
+                exo = ex;
             }
         };
+        public Exception getException(final boolean clear) {
+            final Exception r = exo;
+            if( clear ) {
+                exo = null;
+            }
+            return r;
+        }
     }
 
     public static class WaitAction2 implements Runnable {