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J2ME Introduction
2 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.
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CLDC |
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Native System Software |
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Mobile Information Device |
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Figure 1 Java Platform
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