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J2ME consists of three parts: configuration, profile, and optional packages. The
manufacturers do
not
include the optional packages.
You
have to package and distribute
them
with
your
application.
On
the
other
hands,
the
manufacturers
package
the
other
parts.
JVM is located under the configuration. The Configuration provided by Sun is
Connected
Limited
Device
Configuration
(CLDC) and
Connected
Device
Configuration
(CDC). As the name suggests, CLDC is for the device with limited configuration. This
device has less than 2MB memory available for Java application. The JVM is very
limited and support only
very small subset of
Java
classes. On the other
hand, the CDC
has more memory for Java application. The memory is at least 2MB. This JVM has more
supports, but less than the standard JVM in other platforms.
The Profile provided by Sun is Mobile Information Device Profile (MIDP). The MID
profile complements the CLDC configuration effectively because it minimizes both the
memory and power required for limited devices. The MIDP provide the basic API for
creating the application. The MIDP cannot be used with CDC device. CDC has it own set
of profile, that is the Foundation and Personal profiles. The Latest version of MIDP is 2.0
while the CLDC is 1.1.
2.3.8.2 J2ME Development
There are several things the developer needs to do before he/she can start the
developme nt of J2ME application. Although the device
has prepackaged with JVM and
APIs, we still
need the development kit
to develop
the application.
This development kit
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