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关键词： 应用   移动通信   携带电话机   JAVA语言   程序设计  

ISBN: (数字)7030094425 ISBN: (纸本)7030094425

摘要： 本书主要介绍了如何用Java在PalmOS上编写应用程序，共分为两个部分，第一部分是J2ME的简介，第二部分是PalmOS上Java程序设计.

关键词： JAVA语言   程序设计   CT   S903476   S008424  

关键词： 部分求值,绑定时间分析（BTA）,程序优化  

摘要： 部分求值是一种程序转换技术，它的目的是根据部分输入来例化一个程序。作为程序优化 方法的部分求值技术，通过程序变换把一个具有一般计算功能的程序系统变成为一个专用的程 序系统，提高了程序的执行效率。部分求值技术中一个关键环节就是绑定时间分析（BTA），BTA 的主要目的是在给定的输入条件（已知输入参数的动静态划分）下，把程序结构（变量，表达 式，语句，函数）划分为例化时间已知和运行时间已知，也就是根据程序输入变量的动静态划 分决定程序中其余变量和表达式的动静态划分，判断哪些表达式可以在部分求值时间求值，哪 些在程序运行时求值。绑定时间分析进行的越精确，部分求值的效果就越好，所以说绑定时间 分析在很大程度上影响了部分求值的整体效率。 本文主要介绍了针对Java语言中的部分语句、表达式和数组类型变量的BTA方面的分析、 设计和实现，接着完成了标注程序的生成。最后，通过编写数个有代表性的测试程序例，主要 测试了循环、条件语句以及数组变量的BTA结果以及标注程序的生成。

ISBN: (纸本)7302043086

关键词： security   policy   mobile code   access control   Java   object orientation   binary editing  

摘要： There is considerable interest in programs that can migrate from one host to another and execute, Mobile programs are appealing because they support efficient utilization of network resources and extensibility of information servers. However, since they cross administrative domains, they have the ability to access and possibly misuse a host's protected resources. In this paper, we present a novel approach for controlling and protecting a site's resources. In this approach, a site uses a declarative policy language to specify a set of constraints on accesses to resources, A set of code transformation tools enforces these constraints on mobile programs by integrating the access constraint checking code directly into the mobile program and resource definitions, Using this approach, a site does not need to explicitly include calls to reference monitors in order to protect resources. The performance analysis show that the approach performs better than reference monitor-based approaches in many cases. Copyright (C) 2000 John Wiley & Sons, Ltd.

关键词： ODBC   MFC程序   JAVA程序   套接字   数据交换   INERNET   网络编程语言   数据库   用户界面  

摘要： Internet编程有很多困难 .其中之一是用不同语言编写的程序之间如何实现通讯 ;另一个困　　难是如何利用现有的程序 .本文讨论如何利用ODBC强大功能访问数据库 ,同时建立一个Java程序的用户界面 .

关键词： compiler analysis   parallelism data speculation   dependence analysis  

摘要： Static parallelization of general-purpose programs is still impossible, in general, due to their common use of pointers, irregular data structures, and complex control-flows. One promising strategy is to exploit pa;allelism at runtime. Runtime parallelization schemes, particularly data speculations, alleviate the need to statically prove independent computations at compile-time. However, studies show that many real-world applications exhibit limited speculative parallelism to offset the overhead and penalty of speculation schemes. This paper addresses this issue by using compiler analyses to compensate for speculative parallelizations. We focus on general-purpose Java programs with extensive use of Java container classes. In our scheme, compilers serve as a guideline of where to speculate by "lazily" detecting dependences that are mostly static, while leaving those that are more dynamic to runtime. We also propose techniques to enhance speculative parallelism in the programs. The experimental results show that, after eliminating static dependences, the four applications we study exhibit significant parallelism that can be gainfully exploited by a speculative parallelization system.

关键词： Java   mobile code   security   remote method invocation  

摘要： Mobile code presents a number of threats to machines that execute ii. We introduce an approach for protecting machines and the resources they hold from mobile code and describe a system based on our approach for protecting host machines from Java 1.1 applets. In our approach, each Java applet downloaded to the protected domain is rerouted to a dedicated machine (or set of machines), the playground, at which it is executed. Prior to execution, the applet is transformed to use the downloading user's web browser as a graphics terminal for its input and output and so the user has the illusion that the applet is running on her own machine. In reality, however, mobile code runs only in the sanitized environment of the playground, where user files cannot be mounted and from which only limited network connections are accepted by machines in the protected domain. Our playground thus provides a second level of defense against mobile code that circumvents language-based defenses. The paper presents the design and implementation of a playground for Java 1.1 applets and discusses extensions of it for other forms of mobile code, including Java 1.2.

关键词： Applet Watch-Dog   denial-of-service   antagonism  

摘要： A monitoring application, called (Signed) Applet Watch-Dog, is proposed to control the execution of malicious Java applets that users can (download and) execute during Web surfing. Typical security attacks that the monitor can stop are related to denial-of-service and antagonism (e.g. obscuring the screen), at the price of a modest degradation of the performance of the Web browser. The Applet Watch-Dog described here is the second release, improving over the original version presented in R. Gorrieri, G. Marchetti (Applet Watch-Dog: a monitor controlling the execution of Java applets, in: G. Papp, R. Posch (Eds.), Proceedings of Fourteenth IFIP International Information Security Conference (SEC'98), Chapman Be Hall, London, September 1998). The application is a signed Java applet, to be executed outside of the sandbox, simple to use and easily configurable by the user, because it works like a user interface. Signed Applet Watch-Dog seems also a necessary tool for software development environments for Java applets. (C) 2000 Elsevier Science B.V. All rights reserved.

关键词： API   ATM   jitter   latency   performance evaluation  

摘要： Over the last few years, we have witnessed the emergence of many network-based multimedia applications, particularly those rich in audio, video, and images. Access to network services has become an integral component of these applications. In this paper, we present a Java-based networking Application Programming Interface (API), and compare the performance of our lava-based API with Microsoft Winsock 2 API over different protocols namely, TCP/IP, UDP/IP and native Asynchronous Transfer Mode (ATM). From the results obtained, we observe that the Java layer increases the overall user-to-user latency by about 120 microseconds compared to native Winsock 2 over ATM local area networks. We also found that jitter performance for continuous media applications, such as those involving digital video is highly non-deterministic. We obtained large variations in video jitter over Java, with maximum jitter in the range 6 to 12 milliseconds. (C) 2000 Elsevier Science B.V. All rights reserved.