The Design And Impementation Of Cross-Platform Pushmail Phone Client Platform

Nowadays, there are four major operation systems: Symbian, Windows Mobile, Linux and PalmOS. The operation systems have developed to different editions: Symbian S60 1st,2nd,3rd, Symbian UIQ, Symbian S80 etc., which are based on Symbian; SmartPhone 2002, Pocket PC 2002, SmartPhone 2003, Pocket PC 2003, Windows Mobile 5.0, Windows Mobile 6.0 etc, which are based on Microsoft's WindowsCE; UcLinux,LinuxJava,Ezx base on Linux; and some other editions based on Palm OS, Brew.Each edition has its corresponding supporting soft, which exclusively applies to its corresponding system plat and is useless to any other system plat.Porting software from one OS of platform to another is a way to achieve the software's compatible usage on different operation system or on different platform that from the same OS, but the efforts of maintenance and management is very heavy. Company has to maintain two or more kinds of codes, documents etc. in order to consistency, and there must be different issues on various software which is written under different OS or platform. Therefore, this way brings more maintenance effort and it Increases operation cost of company.This framework includes two parts: Platform Abstract Layer and Mail Services Layer. The Platform Abstract Layer shield the different that be imported by different OS or platform. Mail Service Layer provides services of POP3, SMTP, mail management etc, and defines lots of friendly and clear interface in this layer. The developer can develop application with the unify interfaces. The old service provided by the interface is used well, even if we add new functions or feature or the implement of the interfaces. Event mechanism, cross-platform thread and sync communication also be implement.in Platform Abstract Layer. Friendly UI and the UI transfer logic is the focus of application developer in different OS or platform. Application developing is more effective and faster base on the framework than beore.The key technologies to implement this framework are Abstract Layer and Mail Service Layer.The main functions of Platform Abstract Layer: File IO,memory IO,video playback, audio playback,file description,file attribute,file element,content,time,date,timer and data structure,string,event;The main functions of Mail Service Layer: TCP/IP,POP3,SMTP,IMAP,MIME etc,mail mangment,pre-fetch mangment etc.