Java Reference
In-Depth Information
Figure 1-3.
The relationship between configurations, profiles, and packages in a typical set-
top box or other digial media hardware
Understanding Configurations
The fundamental building block of the Java ME architecture is the configuration.
A configuration defines the Java Virtual Machine ( JVM), basic language support, and
fundamental classes for the widest possible set of devices, such as all mobile wireless
terminals or all set top box-like devices. A specific device must meet the requirements
of at least one configuration, such as the CLDC, in order to qualify as a Java ME device.
Introducing the Connected Limited Device Configuration
The CLDC is explicitly designed for memory-constrained devices that may be always or
intermittently connected to the network. It defines a Java environment based on the Java
K virtual machine (KVM), a modified version of the JVM that has been specially tuned to
operate on low-power devices with a 16- or 32-bit processor and as little as 192KB of
RAM. The most common deployment of the CLDC, as I've already noted, is in the billions
of Java-enabled cell phones that have shipped in the last several years.
