Java Reference
In-Depth Information
•
Configuration
: Defines the basic set of libraries and Java virtual machine (VM) for
a broad range of devices
•
Profile
: Defines a set of APIs for a narrower range of devices
•
Package
: A set of optional APIs that pertain to a specific technology, such as
multimedia or Bluetooth access
Figure 1-1 shows how these abstractions stack to define the software characteristics
of a device.
Figure 1-1.
The relationship between configurations, profiles, and packages in Java ME
Each instance of a configuration, profile, or package
should
have as its basis one or
more Java Specification Requests ( JSRs) that document the purpose and interface for the
Java extension in question. Appendix A summarizes the JSRs relevant to Java ME that
define functionality discussed in this topic.
Today, there are two configurations within Java ME: the Connected Limited Device
Configuration (CLDC) and the Connected Device Configuration (CDC). There are a
handful of profiles that sit atop either of these configurations, and many, many pack-
ages. (In the next section, I explore these configurations in greater detail.)
