CLDC1.0 is launched in October 2000. Subsequent Sun also released MIDP1.0 including the characteristics such as RMS and UI, which is very vibration on the industry, soon some developers have developed the mobile information equipment development. . With the improvement of equipment capabilities, the JSR118 has launched a more powerful MIDP2.0. However, from the development of MIDP1.0, some issues can be seen. Since all APIs provided by CLDC1.0 MIDP 1.0, all vendors have developed their own equipment unique API. At the same time, in order to different functional characteristics of each device, the concept of optional packages, such as Bluetooth, PIM, etc. This causes the API to divide and decrease in degradability.
Since there is no unified standard software operating environment, the split of the API is caused. Developers must query this device to support what functionality to support for some models. What are the standard APIs, which are optional packages and vendor APIs. This undoubtedly brings inconvenience to development.
This makes the privilege of the program greatly reduced by no unified standard specification for the equipment. If you have a program that uses Nokia's API, it's hard to run on other manufacturers' machines. Even if you use a standard API, you have the program to be able to transplant, each manufacturer is different, some is 30K, some is 50K. The extent to which thread support is not the same, some can support 3, some are 5.
The purpose of Java Technology for Wireless Industry is to solve the above two problems, it is proposed in JSR185. JTWI did not propose new technologies and did not provide new APIs. It makes a specification for J2ME's operating environment, providing a more stringent operating environment, which effectively reduces the splitting of the API and improves the portability of the program. JTWI is a basic language class library based on JSR 30 CLDC1.0 based on the specification, but does not support floating point operations. You can use CLDC1.1 to replace 1.0JSR118 MIDP 2.0 provides a support for graphical user interface, persistence storage, GAME, and multimedia. JSR120 WMA1.1 provides short message functionality to support additional mmapi1.0 (jsr135) Optional part. Providing full support for multimedia, the multimedia part in MIDP2.0 is the subset of MMAPI.
JSR185 has specified for some aspects, and implementing JTWI equipment must comply with these specifications.
The size of the standard application must support 64K size applications and 5K JAD files. The size of the persistent storage is 30KB, and the Heap space increases from the 128KB of MIDP 2.0 to 256KB of Notepad function so you can use the pressRegistry's Registeralarm () method JSR185 for the screen size of the device 125 * 125 / 12Bits. The device must support images in JPEG format. HTTP1.1 must be supported by WMA based on WMA, so the device must have a short message transmission and acceptance, JSR185 also stipulates that when the application is ready to send a short message, it is possible to provide the TextField and TextBox components. Browse the user can choose to support mobile multimedia, you must implement MIDI and Mono support If you want to learn more about JSR185, please refer to the following specification
JSR 185, Java Technology for The Wireless Industry JSR 118, MIDP 2.0 JSR 120, Wireless Messaging Architecture 1.1 JSR 135, Mobile Media API 1.1 JSR 135, Mobile Media API 1.1
