Headless support

Since NonStop operating system does not provide support for GUI operations, NSJ 11 is a headless, that conforms to the Oracle's headless support.

NSJ 11 always returns GraphicsEnvironment.isHeadless true. When GraphicsEnvironment.isHeadless returns true, and if your Java programs use classes and methods that require a display, keyboard, sound, or mouse operation, the class or method throws a headless exception.

Classes and methods that support printing, fonts, and imaging are fully supported in a headless JDK.

While the Oracle documentation for the reference implementation states that you must set the system property -Djava.awt.headless=true to run a headless JVM, setting this system property is not required for NSJ 11.

As NSJ 11 is headless, NSJ 11 does not support the AppletViewer tool.