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Rhapsody Developer Release Copyright © 1997 by Apple Computer, Inc. All Rights Reserved.

Rhapsody Developer Release Notes:
Java Virtual Machine

These notes are for the Developer Release 2 (DR2) of the Java^TM virtual machine. The Java virtual machine enables the use of Java programs in Rhapsody. This implementation of the Java virtual machine on Rhapsody platforms is based on the Java Development Kit (JDK) 1.1.5; on Yellow Box for Windows systems, the Java VM is also based on the JDK 1.1.5.

Documentation of the JDK 1.1.5 APIs is available on from Javasoft (http://www.javasoft.com). A subset of the JDK 1.1.5 API documentation is stored on Rhapsody platforms in HTML format in /Library/Frameworks/JavaVM.framework/Documentation/packages.html. JDK 1.1.5 documentation is currently not included on Yellow Box for Windows systems.

Notes Specific to Developer Release

The Java virtual machine consists of two parts:

• An implementation of the Java Development Kit 1.1.5 for Rhapsody.
  
  
• The JavaVM framework, a set of Objective-C classes, used to load and call a virtual machine from Objective C.

Both parts are stored in the /Library/Frameworks/JavaVM.framework directory. (On Yellow Box for Windows platforms, substitute the installation directory ($NEXT_ROOT) for /System.)

New Features

Commands

You can run the following commands, located in /usr/bin, from the command line:

java

Java interpreter, which executes Java programs.

javac

Java language compiler, which translates programs written in Java into bytecodes executable by the Java interpreter .

javah

Creates C header files used to interface programs written in Java with code written in C .

javap

Bytecode disassembler.

jar

Packages multiple files into a Java archive.

javadoc

Generates documentation in HTML format from Java source code.

jdb

Java debugger.

Environment Variables

The Java virtual machine is using the following environment variables:

CLASSPATH

Sets the path to use for looking up class files. If the variable is not defined in the environment, you can set it in a shell script using "javaconfig DefaultClasspath". If javaconfig does not return a class path, the default /System/Library/Java:/Library/Frameworks/JavaVM.framework/Resources/classes.jar is used. (On Windows, substitute the value of NEXT_ROOT for /System).

 

Specifying a class path on the command line overrides this variable. The default is not automatically searched and has to be added to the class path if one is specifed.

 

JAVA_HOME

Sets the java.home property in the system properties. Defaults to /Library/Frameworks/JavaVM.framework/Resources. (On Windows, substitute the value of NEXT_ROOT for /System).

 

JAVA_COMPILER

Sets the java.compiler property in the system properties. Defaults to the empty string.

 

AWT_TOOLKIT

Sets the awt.toolkit property in the system properties. Defaults to com.apple.rhapsody.awt.RToolkit. (This property is not being used in the Developer Release of Rhapsody).

 

DYLD_LIBRARY_PATH

Prefixes the path searched by the Java virtual machine when looking up dynamically loaded libraries. The following directories are always searched in the order they are listed: .:/usr/lib:/lib:/Library/Frameworks/JavaVM.framework/Resources. (On Windows, substitute the value of NEXT_ROOT for /System).

 

Known Problems

• The AWT package has not been implemented for the Developer Release. All Java programs relying on the AWT or parts of it do not execute correctly.
  
  
• On Windows only: After installing Rhapsody, ensure that there is no CLASSPATH variable defined in the System environment or in an AUTOEXEC.BAT file in the root directory of your boot drive. If you have any user-defined class paths, ensure that they are merged correctly into the CLASSPATH variable defined in the User environment.