Analysis of the environments of various application platforms (1)

Here, we will describe the j2m‑based application platforms, which are composed of Configuration and Profile levels. Configuration is the minimum capability and library defined for JVM, make the JVM small enough to run on devices of the same level.

J2-based Platform

The Java2 Platform specifically targets Household Electrical Products and embedded devices. The Java virtual machines and APIs that make up j2's match those running environments for home appliances and embedded products.

It is designed for small devices and has rich user interfaces and network interaction models. It has good programming and portability.

The application platforms of j2s are composed of Configuration) and Profile grade. The Configuration defines the minimum capacity and library for the JVM, so that the JVM is small enough and can run on devices of the same level. Because the configurations of devices at the same level have similar requirements on memory and processing capabilities, the following two types of embedded application devices are divided: one is embedded devices with limited computing functions and limited power supply, such as PDAPersonalDigitalAssistant and mobile phones, which are defined in CLDC specifications; the other is embedded devices with relatively good computing power and adequate power supply, and standardized them into the CDC specification.

A collection of Java-based APIs, which consists of Java class libraries with different functions. The grade is built on the configuration and serves as a supplement to the configuration, providing sufficient runtime environments for specific devices. It aims to better differentiate the functions of Java programs on various embedded devices. Therefore, the class defines the extended classes that are very relevant to specific embedded devices. How to express the application interfaces of Java programs in various embedded devices is implemented through the definition of the class. The extended class libraries defined in each grade are created based on the core class libraries defined in the underlying configuration.