Download Introduction to Java ME

Introduction to Java ME
The Java™ platform is available in three different editions, each optimized for a specific application
environment:

Java Platform, Standard Edition (Java SE)

Java Platform, Enterprise Edition (Java EE)

Java Platform, Micro Edition (Java ME)
The three editions are similar in their fundamental aspects and share the common Java characteristics,
such as automatic garbage collection and cross-platform virtual machine architecture.
Java ME offers a standard framework for developing Java applications for mobile and other embedded
devices, such as mobile phones, and is optimized for an application environment with limited memory
and computing resources. Java ME shares a number of APIs with Java SE and Java EE, so you can
easily adapt your Java programming skills to creating mobile Java applications.
To run Java ME applications, devices must implement a configuration. Configurations specify the
minimum set of Java APIs and virtual machine features required to implement a Java ME runtime
environment. Java ME defines two configurations:

Connected Device Configuration (CDC)

Connected Limited Device Configuration (CLDC)
To provide developers a full platform for creating Java ME applications, devices must also implement a
profile. Profiles sit on top of configurations and specify further Java APIs that focus on specific groups of
devices. Mobile devices use the Mobile Information Device Profile (MIDP) on top of CLDC. MIDP adds
Java APIs specific to resource-constrained devices such as cell phones and PDAs. Any device that
implements a CLDC configuration and a MIDP profile can run Java ME applications developed for any
other device with a corresponding implementation. Java ME applications that use MIDP are called
MIDlets.
In addition to the mandatory CLDC configuration and MIDP profile, mobile devices can support additional
Java APIs for more specific purposes, such as drawing vector graphics, using advanced multimedia
features, or accessing web services.
The following figure provides an overview of the different Java platforms editions.
Figure: Java platform editions