NonStop Server for Java Programmer's Reference (NSJ 4.2+)

example, assume that JNI code, written for a previous version of Java, converts a TNS
floating-point value to a string, which is then passed to Java. To migrate the program, you must
change the JNI code to convert the TNS floating-point value to an IEEE floating-point value
and then call sprintf to convert the floating-point value to a string.
For more information, see IEEE Floating-Point Implementation.
Using AWT Classes
If your Java programs use AWT classes with NonStop Server for Java 3.1.x or earlier versions ,
change your program code to catch a HeadlessException rather than an
UnsupportedClassException.
Because the NonStop Kernel operating system does not provide support for windowing
operations, previous versions of NonStop Server for Java supported only those Abstract
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 JVM 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 JVM and are fully supported by NonStop Server for Java 4.
For further information, see Headless Support in the HP Implementation specifics section.
POSIX Threads
NonStop Server for Java 3.1.x and earlier versions used OSS POSIX threads (product number
T5819) that conformed to an earlier standard (Draft 4) for POSIX threads. Versions 1 and 2 of
NonStop Server for Java use 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.