The Javascript Engine Rhino Research And J2me

Recent years, with the embedded technology developing, embedded platform get great achievements in many aspects, mobile phone and other mobile terminal has a deep impact on people's everyday life. In the history of mobile phone developing, there were several classic stages of development, they are all shown as the cross-functional integration. In the next few years, the mobile phone will gradually complete the transition from an ordinary communication tool to a mobile Internet terminal.Nowadays, mobile business, especially the 3G business emerge more and more quickly. Mobile information search, Online shopping, mobile e-mail, online browsing, high-speed downloads, mobile television, mobile game,and so on, they are all very popular mobile value-added service. The current mainstream mobile phone manufacturer, like Nokia, Motorola, Sony Ericsson, Samsung are all try to enhance their R&D capability of the mobile value-added business. From the platform point of view, Symbian, Windows, Mobile, Linux, BREW, they already provide rich and effective applications platforms, but it is also because of the diversification of the current system platforms and the different development methods, making the application development complexity, long development cycle, single function, and commonality bad. Many providers had to separately develop applications for different platforms. So we are crying out for a new kind of software development platform which can provide novel features, faster developing speed and no need to separately develop. Make various value-added services together to provide a one-stop, personalized service. The Widget technology mentioned in this article is a cutting-edge technology that generated for the demand above.In the process of researching mobile widget, we found the most important module is the JavaScript module which provide the logic and interactivity capability to widget. Because we focus on embedded platform, the JavaScript module's design is aimed at low memory consumption, low cpu requirements and respond quickly to user's operation. Finally we made a design which can support multi-widgets running.The background of this paper is the widget engine project. Start by describing the current status of domestic and foreign research on widget, having an analysis of related technologies, introducing some widget related knowledges. Then, it focuses on the JavaScript engine, especially on the Spidermokey's analysis and comparison. Relying on the introduce of the overall architecture of widget engine, it describes the JavaScript module is in which place of the archecture. Then on the JavaScript module design and implementation carried out a detailed introduction. And it makes a note of the interface design, event handling mechanism, the design of security mechanism. In the development process of this project, we made a use of an advanced development method which names test-driven, it's introduced in the test part of this paper. In order to show out the project's success, I cite two specific examples of widget application, to verify the feasibility and effectiveness of the design and highlight the JavaScript function. At last, it gives an analysis of the value of the subject, the deficience and the improvement measures.