when the quantum toolkit fails to create a pipeline, it does not exit and or report this fatal condition to the application. Normally if an application fails to initialize the connection to the graphical device (in our case the graphics pipeline) then some error is reported so the app can catch and or exit. Think "cannot connect to X Display" kind of thing.

I suggested a System.exit() after the error message:
       final Runnable pipelineRunnable = new Runnable() {
            @Override public void run() {
                if (GraphicsPipeline.createPipeline() == null) {
                    System.err.println("Error initializing prism toolkit: no suitable pipeline found");
 + System.exit(0);

Morris suggested a throwing a RuntimeException("Error initializing prism toolkit: no suitable pipeline found");