NonStop Server for Java Programmer's Reference (NSJ 4.0+)

Windowing Toolkit (AWT) classes and methods that did not require a display, keyboard, sound,
or mouse operation. Any class or method that required such an operation threw an
UnsupportedClassException.
NonStop Server for Java 4 supports the Sun Microsystems enhancement to AWT called
"headless support" that allows a Java VM to indicate whether a display, keyboard, sound, or
mouse operation can be supported in a graphics environment.
Sun implemented headless support by supplying two new methods in the
GraphicsEnvironment class: isHeadless and isHeadlessInstance. In addition,
Sun created a new exception java.awt.HeadlessException. HeadlessException will be
thrown by any class or method that requires a display, keyboard, sound, or mouse operation if
such a class or method is invoked when GraphicsEnvironment.isHeadless returns
true. Classes and methods that support printing, fonts, and imaging are fully supported in a
headless Java VM and are fully supported by NonStop Server for Java 4.
For further information see, Headless Support in the HP Implementation specifics section.
POSIX Threads
Before this current release, NonStop Server for Java used OSS POSIX threads (product number
T5819) that conformed to an earlier standard (Draft 4) for POSIX threads. NonStop Server for
Java 4 uses Standard POSIX Threads (product number T1248), which conforms to IEEE
POSIX Standard 1003.lc.
The use of T1248 by NonStop Server for Java 4 introduces a system dependency on G06.20 or
later.
The pthreads calls in T1248 have changed to conform to the standard; therefore, any native
code that makes pthreads calls might have to change to use the standard pthread routine. For
more information, see Appendix D in the Open System Services Porting Guide, which contains
a list of differences between the pthread routines in T5819 and the routines in T1248.
Additionally, you must change any JNI code that made calls to routines beginning with cma… to
use the Wrapper or Development Toolkit routines (spt….) supplied with T1248.
NOTE: Any user-developed code that makes such pthreads calls must change.
References to bin/oss/posix_threads
If your NonStop Server for Java programs have references to bin/oss/posix_threads in
Pathway configuration files or elsewhere, you must change them to use the NonStop Server for
Java 4 installation bin directory.