Showing papers on "Java Modeling Language published in 2000"

The Real-Time Specification for Java

Abstract: New languages, programming disciplines, operating systems, and software engineering techniques sometimes hold considerable potential for real-time software developers. A promising area of interest-but one fairly new to the real-time community-is object-oriented programming. Java, for example, draws heavily from object orientation and is highly suitable for extension to real-time and embedded systems. Recognizing this fit between Java and real-time software development, the Real-Time for Java Experts Group (RTJEG) began developing the real-time specification for Java (RTSJ) in March 1999 under the Java Community Process. This article explains RTSJ's features and the thinking behind the specification's design. The goal of the RTJEG, of which the authors are both members, was to provide a platform-a Java execution environment and application program interface (API)-that lets programmers correctly reason about the temporal behavior of executing software.

Model Checking JAVA Programs Using Java Pathfinder

Abstract: This paper describes a translator called Java PathFinder (Jpf), which translates from Java to Promela, the modeling language of the Spin model checker. Jpf translates a given Java program into a Promela model, which then can be model checked using Spin. The Java program may contain assertions, which are translated into similar assertions in the Promela model. The Spin model checker will then look for deadlocks and violations of any stated assertions. Jpf generates a Promela model with the same state space characteristics as the Java program. Hence, the Java program must have a finite and tractable state space. This work should be seen in a broader attempt to make formal methods applicable within NASA’s areas such as space, aviation, and robotics. The work is a continuation of an effort to formally analyze, using Spin, a multi-threaded operating system for the Deep-Space 1 space craft, and of previous work in applying existing model checkers and theorem provers to real applications.

Java Language Specification, Second Edition: The Java Series

Abstract: From the Publisher: Written by the inventors of the technology, The Java(tm) Language Specification, Second Edition is the definitive technical reference for the Java(tm) programming language. If you want to know the precise meaning of the language's constructs, this is the source for you. The book provides complete, accurate, and detailed coverage of the syntax and semantics of the Java programming language. It describes all aspects of the language, including the semantics of all types, statements, and expressions, as well as threads and binary compatibility.

Type-based race detection for Java

Abstract: This paper presents a static race detection analysis for multithreaded Java programs. Our analysis is based on a formal type system that is capable of capturing many common synchronization patterns. These patterns include classes with internal synchronization, classes thatrequire client-side synchronization, and thread-local classes. Experience checking over 40,000 lines of Java code with the type system demonstrates that it is an effective approach for eliminating races conditions. On large examples, fewer than 20 additional type annotations per 1000 lines of code were required by the type checker, and we found a number of races in the standard Java libraries and other test programs.

Overview of the IBM Java just-in-time compiler

Abstract: We present the design and implementation of several optimizations and techniques included in the latest IBM JavaTM Just-in-Time (JIT) Compiler. We first discuss some of the modifications we have applied to Sun Microsystems' reference implementation of the Java Virtual Machine (JVMTM) Specification to increase the performance, including a change in the object layout. We then describe each of the optimizations, referring to what had to be taken into account because of both the just-in-time nature of the compiler and the requirements of the Java language specification, such as exception checking. We also present code generation techniques targeting Intel architectures, describing the register allocation schemes, exception handling, and code scheduling. Finally we report on the performance of the IBM JIT compiler, showing both the effectiveness of the individual optimizations and the competitive overall performance of the JIT compiler in comparison with a competitor, using industry-standard benchmarking programs. All the techniques presented here are included in the official product (JIT Compiler version 3.0), which has been integrated into the IBM Developer Kit for WindowsTM, Java Technology Edition, Version 1.1.7.

A certifying compiler for Java

Abstract: This paper presents the initial results of a project to determine if the techniques of proof-carrying code and certifying compilers can be applied to programming languages of realistic size and complexity. The experiment shows that: (1) it is possible to implement a certifying native-code compiler for a large subset of the Java programming language; (2) the compiler is freely able to apply many standard local and global optimizations; and (3) the PCC binaries it produces are of reasonable size and can be rapidly checked for type safety by a small proof-checker. This paper also presents further evidence that PCC provides several advantages for compiler development. In particular, generating proofs of the target code helps to identify compiler bugs, many of which would have been difficult to discover by testing.

Concurrency State Models and Java Programs

Abstract: Jeff Magee and Jeff Kramer John Wiley and Sons, New York, NY, 1999, 374 pp. ISBN 0471987107, $64.99 The book is an introductory text to the ideas, concepts, and topics of concurrency. The text focuses on understanding concepts and techniques, and problems of concurrency, not on the implementation or language. The author's overall goal is that by a combination of learning and doing using Java should make the process of acquiring the skills relating to concurrency interesting, enjoyable, and challenging. The Java language is thus used only for illustration and programming experience of the reader. The book is intended for a computer science student or software developer. A background in programming is expected, as well as some familiarity with the essential concepts of object-oriented programming. Knowledge of the Java programming language and operating systems concepts is beneficial but not required. After reading the text, a reader can expect to have a broad understanding of the concepts of concurrency, the problems that arise, methods to emphasis desirable properties in a concurrent system, and ways to avoid the undesirable ones. The text provides a systematic treatment of concepts, as means to rigorously specify and model concurrent systems, with Java examples to animate and illustrate the concepts discussed. The book is organized into twelve chapters, with three appendices. The first eight chapters provide a concise and comprehensive foundation of concurrency, with the remaining four chapters focusing on more advanced concepts. The latter four chapters are somewhat supplemental and can be read at the discretion of the reader. The content of the text is self-contained, with no reliance upon external references. The authors provide a concluding set of notes and further topics which reference external works, but these are not used in the chapter contents. The introduction provides the foundation for the book, and an idea of what will follow in the rest of the text. The basics of modeling and Java are covered. Authors follow with the concepts of processes, threads and with the idea of concurrency. The emphasis is on using Java, and on the notation used to define a concurrent process or thread. The discussion continues covering interleaving and asynchronous concurrency. Various details about composition of parallel processes and finite state processing modeling are presented. The programming of concurrent execution using Java is then examined via the concept of multiple threads. Here, sharing objects among Java threads is also discussed. The concept of conditional synchronization is covered next, and is used to construct a monitor. The methods of the base object in Java is used, and a waiting queue associated with a Java object is discussed and implemented. This discussion is followed by introduction of deadlock. Authors show the conditions necessary for a deadlock to occur and present an analysis of a concurrent system establishing that such a system is deadlock-free. The classic Dining Philosopher's problem is used to illustrate the distinction between finding deadlocks in models and in programs. The presentation continues with the safety property (that asserts that nothing bad happens), and the liveliness property (that asserts that nothing good happens). Here, authors use the material on model-based design to consolidate many of the concepts previously discussed. No one modeling method or design methodology is emphasized. Then creation and elimination of threads in a running program is covered next. The dynamic starting and stopping of Java threads is presented. The discussion moves then to messaging passing. Asynchronous and synchronous messaging is presented with Java programming examples. The concept of a rendezvous, allowing for interaction in a messaging system, is also presented. Based on the concepts developed so far filter-pipeline, supervisor-worker, and announcer-listener concurrent architectures are examined. Java programs demonstrating how the elements of each model interact at runtime are developed. The presentation completes with modeling and implementing of timed systems. Time is signaled by the passage of successive time ticks. The authors then elaborate on a system that is event-based rather than thread-based. Java programs are used to illustrate in implementation the concepts discussed. The three appendices provide a reference, specification, and listing of semantics for the finite-state modeling algebra used by the authors throughout the book. The text is ideal for teaching in a classroom environment, or for a motivated reader to use for self-paced learning. Its organization follows a logical train of discussion and thought, with each chapter building successively on the other, with the more difficult concepts and topics withheld until later. This gradual approach makes the material flow smoothly and cohesively from the beginning to the end. The book is intended as a textbook, so does organize the material and discussion as one, but does not become too dry or bland to stifle the reader's interest in the material. The examples are inter-mixed with the discussion to highlight and emphasize essential points the authors make in each chapter. The text illustrates concepts well under discussion, and does not become a long-winded recital of theory. The topics examined are fundamental to concurrency, and are well illustrated and discussed, but no one topic is examined extensively. The code examples are well written concerning the programming style, indentation and comments. A CD is provided, containing the codes from the book. In addition supplementary material consisting of presentation slides and an errata is provided on the author's WWW site, as well as on the CD. The book is up to date both on the topics of concurrency, and with the Java applets, code, and programs used to illustrate them. Later, as the Java language evolves, the examples may need to be updated, but for the time being the text well represents that state of the Java language. William F. Gilreath, Micron Technology, Inc., Boise Idaho

JavaML: a markup language for Java source code

Abstract: The classical plain-text representation of source code is convenient for programmers but requires parsing to uncover the deep structure of the program. While sophisticated software tools parse source code to gain access to the program's structure, many lightweight programming aids such as grep rely instead on only the lexical structure of source code. I describe a new XML application that provides an alternative representation of Java source code. This XML-based representation, called JavaML, is more natural for tools and permits easy specification of numerous software-engineering analyses by leveraging the abundance of XML tools and techniques. A robust converter built with the Jikes Java compiler framework translates from the classical Java source code representation to JavaML, and an XSLT stylesheet converts from JavaML back into the classical textual form.

Marmot: an optimizing compiler for Java

Abstract: The Marmot system is a research platform for studying the implementation of high level programming languages. It currently comprises an optimizing native-code compiler, runtime system, and libraries for a large subset of Java. Marmot integrates well-known representation, optimization, code generation, and runtime techniques with a few Java-specific features to achieve competitive performance. This paper contains a description of the Marmot system design, along with highlights of our experience applying and adapting traditional implementation techniques to Java. A detailed performance evaluation assesses both Marmot's overall performance relative to other Java and C++ implementations, and the relative costs of various Java language features in Marmot-compiled code. Our experience with Marmot has demonstrated that well-known compilation techniques can produce very good performance for static Java applications – comparable or superior to other Java systems, and approaching that of C++ in some cases. Copyright © 2000 John Wiley & Sons, Ltd.

jRapture: A Capture/Replay tool for observation-based testing

Abstract: We describe the design of jRapture: a tool for capturing and replaying Java program executions in the field. jRapture works with Java binaries (byte code) and any compliant implementation of the Java virtual machine. It employs a lightweight, transparent capture process that permits unobtrusive capture of a Java programs executions. jRapture captures interactions between a Java program and the system, including GUI, file, and console inputs, among other types, and on replay it presents each thread with exactly the same input sequence it saw during capture. In addition, jRapture has a profiling interface that permits a Java program to be instrumented for profiling o after its executions have been captured. Using an XML-based profiling specification language a tester can specify various forms of profiling to be carried out during replay.

JML: notations and tools supporting detailed design in Java

Abstract: is a notation for specifying the detailed design of Java classes and interfaces. JML's assertions are stated using a slight extension of Java's expression syntax. This should make it easy to use. Tools for JML aid in static analysis, verification, and run-time debugging of Java code.

Guava: a dialect of Java without data races

Abstract: We introduce Guava, a dialect of Java whose rules statically guarantee that parallel threads access shared data only through synchronized methods. Our dialect distinguishes three categories of classes: (1) monitors, which may be referenced from multiple threads, but whose methods are accessed serially; (2) values, which cannot be referenced and therefore are never shared; and (3) objects, which can have multiple references but only from within one thread, and therefore do not need to be synchronized. Guava circumvents the problems associated with today's Java memory model, which must define behavior when concurrent threads access shared memory without synchronization.We present an overview of the syntax and the semantic rules of Guava. We discuss how implementations of Guava can exploit these rules to re-enable compiler optimizations inhibited by standard Java. We discuss how compilers for certain multiprocessor architectures can automatically generate certain programming idioms, such as double-check reads, as optimizations of serialized monitors.

SAFKASI: a security mechanism for language-based systems

Abstract: In order to run untrusted code in the same process as trusted code, there must be a mechanism to allow dangerous calls to determine if their caller is authorized to exercise the privilege of using the dangerous routine. Java systems have adopted a technique called stack inspection to address this concern. But its original definition, in terms of searching stack frames, had an unclear relationship to the actual achievement of security, overconstrained the implementation of a Java system, limited many desirable optimizations such as method inlining and tail recursion, and generally interfered with interprocedural optimization. We present a new semantics for stack inspection based on a belief logic and its implementation using the calculus of security-passing style which addresses the concerns of traditional stack inspection. With security-passing style, we can efficiently represent the security context for any method activation, and we can build a new implementation strictly by rewriting the Java bytecodes before they are loaded by the system. No changes to the JVM or bytecode semantics are necessary. With a combination of static analysis and runtime optimizations, our prototype implementation showes reasonable performance (although traditional stack inspection is still faster), and is easier to consider for languages beyond Java. We call our system SAFKASI (the Security Architecture Formerly Known as Stack Inspection).

Java Program Verification via a Hoare Logic with Abrupt Termination

Abstract: This paper formalises a semantics for statements and expressions (in sequential imperative languages) which includes non-termination, normal termination and abrupt termination (e.g. because of an exception, break, return or continue). This extends the traditional semantics underlying e.g. Hoare logic, which only distinguishes termination and non-termination. An extension of Hoare logic is elaborated that includes means for reasoning about abrupt termination (and side-effects). It prominently involves rules for reasoning about while loops, which may contain exceptions, breaks, continues and returns. This extension applies in particular to Java. As an example, a standard pattern search algorithm in Java (involving a while loop with returns) is proven correct using the proof-tool PVS.

Java programming for high-performance numerical computing

Abstract: First proposed as a mechanism for enhancing Web content, the JavaTM language has taken off as a serious general-purpose programming language. Industry and academia alike have expressed great interest in using the Java language as a programming language for scientific and engineering computations. Applications in these domains are characterized by intensive numerical computing and often have very high performance requirements. In this paper we discuss programming techniques that lead to Java numerical codes with performance comparable to FORTRAN or C, the more traditional languages for this field. The techniques are centered around the use of a high-performance numerical library, written entirely in the Java language, and on compiler technology. The numerical library takes the form of the Array package for Java. Proper use of this package, and of other appropriate tools for compiling and running a Java application, results in code that is clean, portable, and fast. We illustrate the programming and performance issues through case studies in data mining and electromagnetism.

Techniques for obtaining high performance in Java programs

Abstract: This survey describes research directions in techniques to improve the performance of programs written in the Java programming language. The standard technique for Java execution is interpretation, which provides for extensive portability of programs. A Java interpreter dynamically executes Java bytecodes, which comprise the instruction set of the Java Virtual Machine (JVM). Execution time performance of Java programs can be improved through compilation, possibly at the expense of portability. Various types of Java compilers have been proposed, including Just-In-Time (JIT) compilers that compile bytecode into native processor instructions on the fly; direct compilers that directly translate the Java source code into the target processor's native language; and bytecode-to-source translators that generate either native code or an intermediate language, such as C, from the bytecodes. Additional techniques, including bytecode optimization, dynamic compilation, and executing Java programs in parallel, attempt to improve Java run-time performance while maintaining Java's portability. Another alternative for executing Java programs is a Java processor that implements the JVM directly in hardware. In this survey, we discuss the basis features, and the advantages and disadvantages, of the various Java execution techniques. We also discuss the various Java benchmarks that are being used by the Java community for performance evaluation of the different techniques. Finally, we conclude with a comparison of the performance of the alternative Java execution techniques based on reported results.

NaturalJava: a natural language interface for programming in Java

Abstract: NaturalJava is a prototype for an intelligent natural-language-based user interface for creating, modifying, and examining Java programs. The interface exploits three subsystems. The Sundance natural language processing system accepts English sentences as input and uses information extraction techniques to generate case frames representing program construction and editing directives. A knowledge-based case frame interpreter, PRISM, uses a decision tree to infer program modification operations from the case frames. A Java abstract syntax tree manager, TreeFace, provides the interface that PRISM uses to build and navigate the tree representation of an evolving Java program. In this paper, we describe the technical details of each component, explain the capabilities of the user interface, and present examples of NaturalJava in use.

Java design patterns: a tutorial

Abstract: Design patterns have become a staple of object-oriented design and programming by providing elegant, easy-to-reuse, and maintainable solutions to commonly encountered programming challenges. However, many busy Java programmers have yet to learn about design patterns and incorporate this powerful technology into their work.Java™ Design Patterns is exactly the tutorial resource you need. Accessible and clearly written, it helps you understand the nature and purpose of design patterns. It also serves as a practical guide to using design patterns to create sophisticated, robust Java programs.This book presents the 23 patterns cataloged in the flagship book Design Patterns by Gamma, Helm, Johnson, and Vlissides. In Java™ Design Patterns, each of these patterns is illustrated by at least one complete visual Java program. This practical approach makes design pattern concepts more concrete and easier to grasp, brings Java programmers up to speed quickly, and enables you to take practical advantage of the power of design patterns.Key features include: Introductory overviews of design patterns, the Java Foundation Classes (JFC), and the Unified Modeling Language (UML) Screen shots of each of the programs UML diagrams illustrating interactions between the classes, along with the original JVISION diagram files An explanation of the Java Foundation Classes that illustrates numerous design patterns Case studies demonstrating the usefulness of design patterns in solving Java programming problems After reading this tutorial, you will be comfortable with the basics of design patterns and will be able to start using them effectively in your day-to-day Java programming work. 0201485397B04062001

Portable worst-case execution time analysis using Java Byte Code

Abstract: Addresses the problem of performing worst-case execution time (WCET) analysis of Java Byte Code (JBC), which may be generated from different compilers and from different source languages. The motivation for the framework presented is to provide WCET analysis which is portable and therefore more likely to be used in an industrial context. Two issues are addressed in this paper: how to extract data flow and control flow information from JBC programs, and how to provide a compiler-/language-independent mechanism to introduce WCET annotations in the source code. We show that an annotation mechanism based on calls to a static class with empty methods result in similar code when generated by Java or Ada compilers.

Java model checking

Abstract: This paper presents initial results in model checking multi-threaded Java programs. Java programs are translated into the SAL (Symbolic Analysis Laboratory) intermediate language, which supports dynamic constructs such as object instantiations and thread call stacks. The SAL model checker then exhaustively checks the program description for deadlocks and assertion failures, using traditional model checking optimizations to curb the state explosion problem. Most of the advanced features of the Java language are modeled within our framework.

JML (poster session): notations and tools supporting detailed design in Java

Abstract: JML is a notation for specifying the detailed design of Java classes and interfaces. JML's assertions are stated using a slight extension of Java's expression syntax. This should make it easy to use. Tools for JML aid in static analysis, verification, and run-time debugging of Java code.

Understanding the behavior of Java programs

Abstract: To fully understand the underlying architecture of an object oriented software system, both static and dynamic analyses are needed. Dynamic reverse engineering techniques are especially important for understanding the run-time behavior of objects in a distributed object systems and in systems that rely heavily on polymorphism. Shimba, a prototype reverse engineering environment, has been built to support understanding of an existing Java software system. The dynamic event trace information is generated automatically as a result of running the target system under a customized sdk debugger and viewed as scenario diagrams using the SCED tool (K. Koskimies et al., 1998). In SCED, state diagrams can be synthesized automatically from scenario diagrams. This facility is used to visualize the total behavior of a selected object or method, disconnected from the rest of the system. The paper demonstrates how Shimba aids understanding of the behavior of Java programs. A case study is made to validate the usefulness of the approach. The system under investigation is the FUJABA environment, consisting of almost 700 Java classes.

Process Oriented Design for Java: Concurrency for All.

Abstract: Concurrency is thought to be an advanced topic - much harder than serial computing which, therefore, needs to be mastered first. This seminar contends that this tradition is wrong, which has radical implications for the way we educate people in Computer Science - and on how we apply what we have learnt.A process-oriented design pattern for concurrency is presented with a specific binding for Java. It is based on the algebra of Communicating Sequential Processes (CSP) as captured by the JCSP library of Java classes. No mathematical sophistication is needed to master it. The user gets the benefit of the sophistication underlying CSP simply by using it.Those benefits include the simplification wins we always thought concurrency should generate. Although the Java binding is new, fifteen years of working with students at Kent have shown that the ideas within process-oriented design can be quickly absorbed and applied. Getting the ideas across as soon as possible pays dividends - the later it's left, the more difficult it becomes to wean people off serial ways of thought that often fit applications so badly. Concurrency for all (and for everyday use) in the design and implementation of complex, maintainable and scalable computer systems is both achievable and necessary.

Deterministic replay of distributed Java applications

Abstract: Execution behavior of a Java application can be nondeterministic due to concurrent threads of execution, thread scheduling, and variable network delays. This nondeterminism in Java makes the understanding and debugging of multi-threaded distributed Java applications a difficult and a laborious process. It is well accepted that providing deterministic replay of application execution is a key step towards programmer productivity and program under-standing. Towards this goal, we developed a replay framework based on logical thread schedules and logical intervals. An application of this framework was previously published in the context of a system called Deja Vu that provides deterministic replay of multi-threaded Java programs on a single Java Virtual Machine (JVM). In contrast, this paper focuses on distributed Deja Vu that provides deterministic replay of distributed Java applications running on multiple JVMs. We describe the issues and present the design, implementation and preliminary performance results of distributed Deja Vu that supports both multi-threaded and distributed Java applications.

The Java memory model is fatally flawed

Abstract: The Java memory model described in Chapter 17 of the Java Language Specification gives constraints on how threads interact through memory. This chapter is hard to interpret and poorly understood; it imposes constraints that prohibit common compiler optimizations and are expensive to implement on existing hardware. Most JVMs violate the constraints of the existing Java memory model; conforming to the existing specification would impose significant performance penalties. In addition, programming idioms used by some programmers and used within Sun's Java Development Kit is not guaranteed to be valid according to the existing Java memory model.Furthermore, implementing Java on a shared-memory multiprocessor that implements a weakmemory model poses some implementation challenges not previously considered. Copyright © 2000 John Wiley & Sons, Ltd.

Jam : A smooth extension of Java with mixins

Abstract: In this paper we present Jam, an extension of the Java language supporting mixins, that is, parametric heir classes. A mixin declaration in Jam is similar to a Java heir class declaration, except that it does not extend a fixed parent class, but simply specifies the set of fields and methods a generic parent should provide. In this way, the same mixin can be instantiated on many parent classes, producing different heirs, thus avoiding code duplication and largely improving modularity and reuse. Moreover, as happens for classes and interfaces, mixin names are reference types, and all the classes obtained instantiating the same mixin are considered subtypes of the corresponding type, hence can be handled in a uniform way through the common interface. This possibility allows a programming style where different ingredients are mixed together in defining a class; this paradigm is somehow similar to that based on multiple inheritance, but avoids the associated complications. The language has been designed with the main objective in mind to obtain, rather than a new theoretical language, a working and smooth extension of Java. That means, on the design side, that we have faced the challenging problem of integrating the Java overall principles and complex type system with this new notion; on the implementation side, that we have developed a Jam to Java translator which makes Jam sources executable on every Java Virtual Machine.

Java server performance: a case study of building efficient, scalable Jvms

Abstract: The importance of the JavaTM platform has shifted from a client-centered paradigm to the server. In particular, the Java language has matured into a viable programming model for server applications. Correspondingly, the requirements on the Java virtual machine (Jvm) have shifted. This paper details the serverspecific performance enhancements made to the core Jvm and just-in-time (JIT) compiler, which have allowed the IBM Developer Kits that implement Java code for Intel processors to become industry performance leaders. The paper focuses on synchronization implementation and granularity improvements that have greatly increased the scalability of the Java language on multiprocessor machines. Focus is also given to memory management, specifically, object allocation, garbage collection, and heap management. Details of communication and connection scaling are also provided. Finally, server-specific enhancements to the JIT compiler are discussed. All component enhancements in the paper are explained, and their performance implications are quantified with results from representative multithreaded server workloads. The paper summarizes work from across IBM. The authors' specific contributions include the three-tier spin lock, the thread local heap and freelist merge, the dynamic heap growth algorithm, bitwise sweep, compaction avoidance, and the suite of network enhancements.

Jam - A Smooth Extension of Java with Mixins

Abstract: In this paper we present Jam, an extension of the Java language supporting mixins, that is, parametric heir classes A mixin declaration in Jam is similar to a Java heir class declaration, except that it does not extend a fixed parent class, but simply specifies the set of fields and methods a generic parent should provide In this way, the same mixin can be instantiated on many parent classes, producing different heirs, thus avoiding code duplication and largely improving modularity and reuse Moreover, as happens for classes and interfaces, mixin names are reference types, and all the classes obtained instantiating the same mixin are considered subtypes of the corresponding type, hence can be handled in a uniform way through the common interface This possibility allows a programming style where different ingredients are "mixed" together in defining a class; this paradigm is somehow similar to that based on multiple inheritance, but avoids the associated complications The language has been designed with the main objective in mind to obtain, rather than a new theoretical language, a working and smooth extension of Java That means, on the design side, that we have faced the challenging problem of integrating the Java overall principles and complex type system with this new notion; on the implementation side, that we have developed a Jam to Java translator which makes Jam sources executable on every Java Virtual Machine

Computer-implemented method for generating a UML representation from JAVA source code

Abstract: A computer-implemented method for representing JAVA in UML in a computer system executing a repository program. The method comprises the steps of determining if a file is a JAVA package or project. If it is, then determining if there is a JAVA subpackage not represented in UML, and if so; recursively creating UML subpackages representing each nested JAVA subpackage. If it is determined that the file is not a JAVA package or project, then the method creates UML files representing each JAVA source file.

A CSP model for Java multithreading

Abstract: Java threads are synchronised through primitives based upon monitor concepts developed in the early 1970s. The semantics of Java's primitives have only been presented in natural language-this paper remedies this with a simple and formal CSP model. In view of the difficulties encountered in reasoning about any non-trivial interactions between Java threads, being able to perform that reasoning in a formal context (where careless errors can be highlighted by mechanical checks) should be a considerable confidence boost. Further automated model-checking tools can be used to root out dangerous states (such as deadlock and livelock), find overlooked race hazards and prove equivalence between algorithms (e.g. between optimised and unoptimised versions). A case study using the CSP model to prove the correctness of the JCSP channel implementation (which is built in terms of standard Java monitor synchronisations) is presented.