NonStop Server for Java 5.1 Programmer's Reference

Headless Support
Because the HP NonStop operating system does not provide support for windowing operations, NonStop Server
for Java 5.1 is a headless JVM that conforms to the Sun Microsystems headless support standard regarding Java
Abstract Window Toolkit (AWT) classes and methods. For similar reasons, the NonStop Server for Java 5.1 does
not support the AppletViewer tool.
If your Java programs use classes and methods that require a display, keyboard, sound, or mouse operation, the
class or method will throw a HeadlessException if invoked when
GraphicsEnvironment.isHeadless returns true. This value is always true in NonStop Server for Java 5.1.
Classes and methods that support printing, fonts, and imaging are fully supported in a headless JVM.
While the Sun Microsystems 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 unnecessary
for NonStop Server for Java 5.1.
The following J2SE features are not applicable (and, therefore, not available):
Class data sharing (CDS), a feature intended to reduce application startup time and footprint, that is
available only with a Java HotSpot client VM.
Server-class machine detection because a server-class machine is always assumed
Java user-interface features because they are desk-top related
General deployment features, such as klist
Java Web Start Technology
Sound Java API
ThreadDumpPath Support
By default, sending the Java process a SIGQUIT signal results in a thread dump being written to stdout.
Starting with the Java 5.1 T2766H51^ABW release, the -XX:ThreadDumpPath=<path/filename> option
can be used to specify the thread dump file name or directory where the thread dump is created.
Additional Files
In addition to the standard Java packages, the NonStop Server for Java 5.1 provides these files:
jtatmf.jar
File containing classes for the version of the NonStop Java Transaction Agent that uses TMF
javachk
The Java Checker program, which determines whether a problem with the JVM is caused by an incorrect
TCP/IP configuration