What is Java 2 Micro Edition?

Java is known primarily as a server-side programming environment, centered around the technologies that make up the Java 2 Enterprise Edition (J2EE), such as Enterprise JavaBeans (EJBs), servlets, and JavaServer pages (JSPs). Early adopters of Java, however, will recall that it was originally promoted as a client-side application environment. In fact, Java was originally designed as a programming language for consumer appliances. Now Java is returning to its roots with Java 2 Micro Edition, or J2ME for short.



The Java 2 Platform
What we commonly refer to as "Java" is more formally known as the Java 2 Platform. The Java 2 Platform is split into three editions: Java 2 Standard Edition (J2SE), Java 2 Enterprise Edition (J2EE), and Java 2 Micro Edition (J2ME). Each edition of the platform provides a complete environment for running Java-based applications, including the Java virtual machine (VM) and runtime classes.

Java 2 Micro Edition
In J2ME, the Java runtime environment is adapted for constrained devices - devices that have limitations on what they can do when compared to standard desktop or server computers. For low-end devices, the constraints are fairly obvious: extremely limited memory, small screen sizes, alternative input methods, and slow processors. High-end devices have few, if any, of these constraints, but they can still benefit from the optimized environments and new programming interfaces that J2ME defines.