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JVM Programming DESCRIPTION Java programs are compiled into bytecode which is independent of the underlying computer architecture. The resulting compiled classes can run on any Java virtual machine (JVM). The JANOS JVM is a 'clean-room' implementation developed entirely from 'The Java(tm) Virtual Machine Specification' written by Tim Lindholm and Frank Yellin published by Addison Wesley Longman, Inc. Copyright (c) 1997 Sun Microsystems, Inc. Each application program is executed by its own instance of JVM. Each appears as a separate process. Each program may have any number of independently running threads. As JANOS can execute as many as 16 separate processes and understanding that several processes need be reserved for network and system activity, JANOS can reliably run several instances of the JVM getting the job done for you. RUNTIME Java is a class-based, object-oriented programming language. The java.lang.Object is the root of the entire Java class hierarchy. Every class has Object as a superclass. The /etc/JanosClasses.jar file located on every JNIOR in read-only memory contains the necessary java.* class library as well as additional libraries as are necessary for programs to interface to JNIOR hardware and the rest of the world. To be successful, application programs developed for JNIOR must be built entirely on JanosClasses.jar and not with respect to any libraries that might otherwise be installed in combination with the IDE and compiler you use. The JanosClasses.jar file may be uploaded from the JNIOR and specified in the -bootclasspath option to the compiler. A program built in this way is guaranteed to have everything it needs to run reliably without Exception on any JNIOR. The JanosRuntime_2.0.jar runtime library file can separately be obtained from the INTEG website at jnior.com . This file contains the same class libraries that are available in JanosClasses.jar, additionally including Javadoc and source code detail to support development using an IDE. While either file will generate the same program the latter is invaluable in getting the most out of your IDE and JNIOR. NOTES Programs access JNIOR hardware and other capabilities using a low-level native interface. A optimized call-by-name method is used permitting the operating system to be freely updated without creating a need to recompile application programs. Once a built-in method is located its location is cached and programs execute fast and efficiently. SEE ALSO HELP Topics: COMPILING, PROGRAMMING, JanosClasses.jar [/flash/manpages/program.hlp:23]