 - A Java virtual machine (JVM), an implementation of the Java Virtual Machine Specification, interprets compiled Java binary code (called bytecode) for a computer's processor (or "hardware platform") so that it can perform a Java program's instructions. Java was designed to allow application programs to be built that could be run on any platform without having to be rewritten or recompiled by the programmer for each separate platform. A Java virtual machine makes this possible because it is aware of the specific instruction lengths and other particularities of the platform.
The Java Virtual Machine Specification defines an abstract -- rather than a real -- machine or processor. The Specification specifies an instruction set, a set of registers, a stack, a "garbage heap," and a method area. Once a Java virtual machine has been implemented for a given platform, any Java program (which, after compilation, is called bytecode) can run on that platform. A Java virtual machine can either interpret the bytecode one instruction at a time (mapping it to a real processor instruction) or the bytecode can be compiled further for the real processor using what is called a just-in-time compiler.
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Learn more about Java Web Services |
| JavaOne: JBoss on SOA middleware, Java EE and data services: Is SOA middleware that different from traditional middleware? At JavaOne, Red Hat's Craig Muzilla ponders that and the future of Java EE and data services. |
| Java One: Mule architect looks to bring REST to SOA: In a conversation at JavaOne, MuleSource's Dan Diephouse, talks about his work on Mule Galaxy, the REST-based open source registry/repository that is going GA later this month. |
| Mule architect sees REST with Atom rising, UDDI fading: Dan Diephouse, the creator of XFire and software architect at MuleSource Inc., discusses the advantages in using REST and the Atom Publishing Protocol. |
| Oracle links SOA, data services, BI and BAM: When it comes to incorporating data services, business intelligence (BI), and business activity monitoring (BAM), Oracle has not lost sight of its database roots. |
| Eclipse, Sun and Oracle team up on persistence API: The surprise announcement from EclipseCon, is Sun Microsystems. selecting the Oracle led EclipseLink project as the reference implementation for the Java Persistence API 2.0. |
| JavaOne news: A collection of SOA and Web services news related articles from the JavaOne conference held in San Francisco. |
| 2006 JavaOne coverage: A compilation of stories written about the JavaOne conference held in San Francisco this past May. |
| Chapter of the week: Security and Ajax: This chapter, excerpted from Ajax in Action, discusses security-related concerns that have particular implications for Ajax. |
| Chapter of the week: Working with Beehive Web services and JSR 181: This chapter, excerpted from Pro Apache Beehive, explores the Web service capabilities that are a part of Apache Beehive. You'll learn about JSR 181, Web Services Metadata for the Java ... |
| Decision time: .NET or J2EE?: How do .NET and J2EE stack up against one another? That depends on who you ask. We've compiled resources from both sides of the fence to help you decide for yourself. |
| LAST UPDATED: |
22 Sep 2006
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