Motorola C381P 用户手册

2
J2ME Introduction

J2ME Introduction

The Motorola C381p handset includes the Java™ 2 Platform, Micro Edition, also known
as the J2ME platform. The J2ME platform enables developers to easily create a variety of
Java applications ranging from business applications to games. Prior to its inclusion,
services or applications residing on small consumer devices like cell phones could not be
upgraded or added to without significant effort. By implementing the J2ME platform on
devices like the Motorola C381p handset, service providers, as well as customers, can
easily add and remove applications allowing for quick and easy personalization of each
device. This chapter of the guide presents a quick overview of the J2ME environment and
the tools that can be used to develop applications for the Motorola C381p handset.

The Java 2 Platform, Micro Edition (J2ME)

The J2ME platform is a new, very small application environment. It is a framework for the
deployment and use of Java technology in small devices such as cell phones and pagers.
It includes a set of APIs and a virtual machine that is designed in a modular fashion
allowing for scalability among a wide range of devices.
The J2ME architecture contains three layers consisting of the Java Virtual Machine, a
Configuration Layer, and a Profile Layer. The Virtual Machine (VM) supports the
Configuration Layer by providing an interface to the host operating system. Above the VM
is the Configuration Layer, which can be thought of as the lowest common denominator of
the Java Platform available across devices of the same “horizontal market.” Built upon this
Configuration Layer is the Profile Layer, typically encompassing the presentation layer of
the Java Platform.

Mobile Information Device

Native System Software

CLDC

MIDP

OEM
Classes

MIDP-Compliant

Apps

OEM
Apps

Native
Apps