Posted by Wade Walker on Dec 20, 2010; 10:52pm
URL: https://forum.jogamp.org/NullPointerException-on-GLCanvas-dispose-tp1212161p2123067.html

Is it really that simple? It looks like when you specify JFrame.DO_NOTHING_ON_CLOSE, you're supposed to dispose the window in the windowClosing event (see here). Maybe the GLCanvas doesn't respect the DO_NOTHING_ON_CLOSE properly?