These groupings
are needed to tailor the Java technology to different areas of today??™s
vast computing industry. Figure 1.6 illustrates the Java platform editions
and their target markets.
The Java ME platform brings the power and benefits of Java technology
(code portability, object-oriented programming, and a rapid
development cycle) to consumer and embedded devices. The main goal
of Java ME is to enable devices to dynamically download applications
that leverage the native capabilities of each device. The Consumer and
embedded space covers a range of devices from pagers to television settop
boxes that vary widely in memory, processing power, and I/O capabilities.
To address this diversity, the Java ME architecture defines
14 Chapter One: Introduction
configurations, profiles, and optional packages to allow for modularity
and customizability. Figure 1.7 shows the high-level relationship
between layers of the Java ME architecture. The layers are explained
further in the next section.
1.4.1 Configurations
A Java virtual machine interprets the Java byte codes generated when
Java programs are compiled. A Java program can be run on any device
that has a suitable virtual machine and a suitable set of Java class
libraries.
JVM Card VM KVM
Java Enterprise Edition
(Java EE)
Java Standard Edition
(Java SE)
Connected Device
Configuration (CDC)
Optional packages
Servers and enterprise
computers
Optional packages
Desktop and personal
computers
Foundation Profile
Personal Profile
Optional packages
High end consumer
devices
Connected
Limited Device
Configuration
(CLDC)
Mobile
Information
Device Profile
(MIDP)
Optional
packages
Low end consumer
devices
Smart Card
Profile
Smart cards
Java Micro Edition
(Java ME)
Figure 1.
Pages:
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53