Article

Multimedia support for J2ME on high-end PDAs - art. no. 65070B

February 2007
Proceedings of SPIE - The International Society for Optical Engineering

DOI:10.1117/12.713932

Authors:

Brandenburg University of Applied Sciences

University of Bedfordshire

Platform independence is the major advantage of the Java programming language. Whereas Java is widespread on servers, desktop computers and mobile phones. In contrast, PDA and Pocket PC applications are usually based on C or C# applications in the .NET Compact Framework. The paper focuses on the J2ME standard and its suitability for Pocket PCs and PDA. In that context we also give an overview of existing Java Virtual Machines (JVMs). In particular we evaluate Esmertecs Jbed CDC, IBM Websphere Everyplace, Creme and MySaifu and compare them according to functional criteria as well as standard conformance and performance. Furthermore a set of tests to benchmark these different JVMs is given. Finally, An example application is implemented, as part of the Bosporus project, to evaluate the JVMs from the programmers perspective.

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January 2005 · ACM SIGPLAN Notices

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Chapter

Chapter 1: Beginning C++

January 2015

Bruce Sutherland

The C++ programming language is a powerful low-level language that allows you to write programs that are compiled into machine instructions to be executed on a computer’s processor. This makes C++ different from newer languages such as C# and Java. These languages are interpreted languages. This means they are not executed directly on the processor but instead are sent to another program that is ... [Show full abstract] responsible for operating the computer. Java programs are executed using the Java virtual machine (JVM), and C# programs are executed by the Common Language Runtime (CLR).

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A web-based surveillance system for mobile phones

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MoonWalker is a software model checker for cil bytecode programs, which is able to detect deadlocks and assertion violations in cil assemblies, better known as Microsoft .NET programs. The design of MoonWalker is inspired by the Java PathFinder (jpf), a model checker for Java programs. The performance of MoonWalker is on par with jpf. This paper presents the new version of MoonWalker and ... [Show full abstract] discusses its most important features. This paper presents MoonWalker† 1.0 (18), a software model checker for the verification of cil bytecode programs. cil stands for Common Intermediate Language and is the platform independent bytecode used within Microsoft's .Net. MoonWalker targets programs compiled against the Mono development platform (16), an open source implementation of the .Net development platform. MoonWalker is a software model checker that uses the virtual machine ap- proach of verification: the effect of every cil bytecode instruction is analysed by the tool. MoonWalker systematically explores all reachable states of the appli- cation under verification, which involves executing bytecode instructions, stor- ing and restoring states, and checking for safety properties. During exploration, MoonWalker will check for deadlocks and assertion violations. The approach of MoonWalker is inspired by the Java PathFinder (jpf) (12, 15), a very successful software model checker for Java. jpf pioneered the con- cept of implementing a software model checker around a virtual machine. And although the object-oriented design and the actual implementation of Moon- Walker (in C#) and organisation of the classes and algorithms are different, all credits for the verification approach should go to the developers of jpf. With MoonWalker 1.0, however, there is now a competitive software model checker readily available for the .Net framework. An important advantage of cil over Java bytecode is that cil has been designed to be the target for many programming languages, not just C#. See (17) for a complete overview. Finally, version 1.0 of MoonWalker incorporates some new techniques not yet available in other model checkers. xrt (5) is an alternative software model checker for .Net, which follows the same approach as jpf. xrt is not publicly available. † MoonWalker was previously known as mmc: the Mono Model Checker.

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June 2003 · Science of Computer Programming

To study the properties of the Java Virtual Machine (JVM) and Java programs, our research group has produced a series of JVM models written in a functional subset of Common Lisp. In this paper, we present our most complete JVM model from this series, namely, M6, which is derived from a careful study of the J2ME KVM [Connected Limited Device Configuration (CLDC) and the K Virtual Machine, ... [Show full abstract] http://java.sun.com/products/cldc/] implementation.On the one hand, our JVM model is a conventional machine emulator. M6 implements dynamic class loading, class initialization and synchronization via monitors. It executes most J2ME CLDC Java programs that do not use any I/O or floating point operations. Engineers may consider M6 an implementation of the JVM. The June 2003 version is implemented with around 10K lines of Lisp in 28 modules.On the other hand, M6 is novel because it allows for analytical reasoning in addition to conventional testing. M6 is written in an applicative (side-effect free) subset of Common Lisp, for which we have given precise meaning in terms of axioms and inference rules. Properties of M6 and its bytecoded programs can be expressed as formulas and proved as theorems. Proofs are constructed interactively with a mechanical theorem prover. Its concreteness, completeness, executability and mechanized reasoning support make our model unique among JVM models.We argue that our approach of building an executable model of the system with an axiomatically described functional language can bring benefits from both the testing and the formal reasoning worlds.

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Last Updated: 22 Oct 2024