JAVA CARD多任务切换机制实现及应用  

Implementation and Application of JAVA CARD Multi-task Context Switch Mechanism

作　　者：王博然[1,2] 周祥 

机构地区：[1]北京工业职业技术学院,北京100042 [2]北方工业大学,北京100041 [3]电信科学与技术研究院(北京),北京100083

出　　处：《北京工业职业技术学院学报》2010年第1期27-33,共7页Journal of Beijing Polytechnic College

摘　　要：作为在智能卡平台上运行的Java虚拟机,受限于硬件资源,目前还只能以传统的单进程、单任务的机制运行。即使在具备多逻辑通道的卡上,虚拟机之上的Applet应用程序都是在APDU的触发下开始执行,其他Applet只有在其执行完成后才可以开始执行。单个APDU会话周期中只允许一个Applet应用程序执行。提出一种对卡上Java虚拟机的改造方案,来实现多个Applet以并发任务的状态共存、相互间中断并切换执行的机制,而后描述了这种机制的优点和多个应用场景,并就其局限性和优化进行讨论。Java Card is the smallest version of Java, which is running on the smart card platform. Java Cardis now single - process and single - task capable because of the restriction of smart card hardware. Either on the single logical channel or multi logical channel Java Card, the Java Card application named Applet can onlybe triggered by APDU and other Applets can not run until the exit of the current running Applet. No more than one Applet can be active during a single APDU session. This paper presents an upgrading solution of traditional Java Card Virtual Machine, in which we implement the mechanism of multi Applet tasks＇ coexistence and context switch. Then the advantages and application scenarios of this kind of mechanism are listed. At last we illustrate the limitations, optimization ideas and the prospect.

关 键 词：JAVA CARD 并发多Applet任务 上下文切换 Java栈 

分 类 号：TP391.7[自动化与计算机技术—计算机应用技术]