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Java virtual machines

This page gives an overview of Java virtual machines (JVM), Java development kits (JDK), Java runtime environments (JRE) and related products. There are four pages with lists of product links:

• List of Java development kits and Java runtime environments,
• standalone Java virtual machines,
• Java products for embedded systems and
• Just-in-time (JIT) compilers.

There is a page of its own on Java compilers. You want me to add or update an entry on this page? Please read these remarks first!

Related links

• Alternative Java Implementations — by David K. Friedman and David A. Wheeler.
• Embedded JVMs and native compilers — list of links.
• Open Directory — a web directory; Java Implementations entry.
• Yahoo! directory — a web directory: Java VM entry.

Things to consider

Note that you will have to regard a few points when choosing a virtual machine or compiler:

• What platform (operating system, underlying hardware) are you using?
• How important is execution speed? Do you want to use the common approach of interpreted bytecode or do you want to create machine code from your Java programs? What about a just-in-time (JIT) compiler that converts (part of) the bytecode to native code when necessary?
• Which edition of Java is required for your programs? Sun has come up with a micro, a standard and an enterprise edition. Version numbers range from 1.02 to 1.5 beta. There are PersonalJava and EmbeddedJava, designed to run in environments with limited resources.
• Do you need real-time capabilities?
• Do you want a virtual machine that is integrated in the operating system?
• Do you want Java as defined in the Java Language Specification, or do you need a subset or superset of language features?
• What distribution model do you want, how much money can you spend - the products listed on the four pages linked to above range from commercial to GPL'd, prices from several thousand US dollars to free.