Due to the preeminent work of the real-time specification for java(RTSJ), java is increasingly expected to become the leading programminglanguage in real-time systems. To provide a java platform suitable for real-tim...
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ISBN:
(纸本)1595934804;9781595934802
Due to the preeminent work of the real-time specification for java(RTSJ), java is increasingly expected to become the leading programminglanguage in real-time systems. To provide a java platform suitable for real-time applications, a real-time java processor can execute java bytecode directly is proposed in this paper. This processor provides efficient support in hardware for mechanisms specified in the RTSJ and offers a simpler programming model through ameliorating the scoped memory of the RTSJ. The most important characteristic of the processor is that its WCET(worst case execution time) of the bytecode execution is predictable. It is vital for the real-time systems. Copyright 2007 ACM.
The jLab system implements a Scilab like scripting language. This language, called jMath is executed by an interpreter written in the javalanguage. The jMath language supports all the basic programming constructs and...
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The jLab system implements a Scilab like scripting language. This language, called jMath is executed by an interpreter written in the javalanguage. The jMath language supports all the basic programming constructs and adopts a SciLab like syntax. Also, an extensive set of built in mathematical routines that cover all the basic numerical analysis tasks is provided. The toolboxes of jLab can be implemented either with jMath, or directly in java. The later approach offers implementation efficiency and scalability while the former is adequate for time demanding modules and initial algorithm development. The corresponding java classes can be dynamically integrated to the system. The efficiency of the java compiled code can be directly utilized for any computationally intensive operations. Since jLab is coded in pure java the build from source process is much cleaner, faster, platform independent and less error prone than similar C/C++/Fortran based open source environments (e.g. Scilab, Octave).
Set, a collection of distinct values, is widely used in many applications. There are three applicable set classes included in the java Collections. TreeSet produces a sorted output in ascending order whereas HashSet p...
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Set, a collection of distinct values, is widely used in many applications. There are three applicable set classes included in the java Collections. TreeSet produces a sorted output in ascending order whereas HashSet provides an output with random order. LinkedHashSet, a subclass of HashSet, produces an output in insertion order, but does not support the sorted output. Three algorithms are proposed in this paper to modify the existing set classes in the java Collections so that they can provide multiple output formats for users to select from. The algorithm at application-level does not change the current configurations of the set classes, but it is offers little reusability. The algorithm at method level introduces an internal method for producing sorted output into the LinkedHashTable class, in addition to its default output in insertion order. This can be achieved without change other configurations of the class. If this method is placed in the HashSet class, users can freely choose their preferred output format from random order, insertion order, or ascending order. The algorithm at class level proposes a new LinkedTreeSet class that is implemented using both a balanced BST and a doubly linked list. The basic operations of this class may be slightly slower than that in the TreeSet class.
AJAX (Asynchronous javaScript and XML), which represents an entire new paradigm in Web design, enables a design style that is more dynamic and more interactive. The primary technological breakthrough that enabled AJAX...
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AJAX (Asynchronous javaScript and XML), which represents an entire new paradigm in Web design, enables a design style that is more dynamic and more interactive. The primary technological breakthrough that enabled AJAX is XmlHttpRequest (XHR), or XMLHTTP ActiveX object, an equivalent mechanism from Microsoft. The various libraries that assist in the development of pages using AJAX include Yahoo!UI Library, Google Web Toolkit, or Dojo Toolkit. AJAX is great at solving two problems in traditional page-based Web design that include buffering data before the user needs it, and improving user inter-activity with the application interface. AJAX-style programming offers less bandwidth requirements as data that is needed is requested and transferred, while refreshing the entire page will all data and graphics is not necessary. It also helps in making a request in the background, while the user has continuous ability to interact with the page.
java is not a secure language and its increasing use puts sensitive information at risk. While the authors do not recommend java software that involves sensitive information, the current reality is that java is used i...
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java is not a secure language and its increasing use puts sensitive information at risk. While the authors do not recommend java software that involves sensitive information, the current reality is that java is used in these applications. To address this reality, this article discusses java obfuscation techniques.
Mixed languageprogramming is very useful for many applications which can take advantage of the salient features of different programminglanguages. In this paper, design and Implementation of Chjava which supports po...
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ISBN:
(纸本)0780397215
Mixed languageprogramming is very useful for many applications which can take advantage of the salient features of different programminglanguages. In this paper, design and Implementation of Chjava which supports portable mixed languageprogramming In C/C++ and java will be presented. Chjava integrates portable C/C++ interpreter Ch and java virtual machine. Using Chjava, java classes can be executed from a C/C++ program interpretiely, and C/C++ programs can be executed from a java program. Chjava contains the salient features of both C/C++ and java. The application of Chjava in interactive control of a mechatronic system is presented. The mechatronic system can be controlled in a standalone environment. It can also be controlled across internet through a Web browser with the program running either in a client side or In a Web server. In this application, the control of C/C++ scripts can be generated and modified dynamically. It is expected that Chjava will find applications in many different fields.
Some important problems in information security such as software protection, watermarking and obfuscation have been proved to be impossible to solve with software-based solutions. By protecting certain actions in orde...
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ISBN:
(纸本)9783540744085
Some important problems in information security such as software protection, watermarking and obfuscation have been proved to be impossible to solve with software-based solutions. By protecting certain actions in order to guarantee that they are executed as desired, trivial solutions to those problems can be implemented. For tamperproof hardware devices such as smart cards to serve this purpose they must provide the capability to execute code on-the-fly. This paper presents mechanism to allow dynamic code execution in java Card in order for these cards to be used in software protection problems. However, the solution can be used in other applications.
One very important aspect of computer programming is reading source code. Whilst this is a relatively simple process for sighted programmers, for blind computer programmers this presents a significant problem. Navigat...
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ISBN:
(纸本)9783540732822
One very important aspect of computer programming is reading source code. Whilst this is a relatively simple process for sighted programmers, for blind computer programmers this presents a significant problem. Navigating through and comprehending often thousands of lines of code can be time consuming and difficult. Current development environments have many features that aid the reading of source code for sighted users, however, most of these features are visual in nature and are not translated well into audio by general screen-reader applications. Research has suggested that the use of fisheye views could aid navigation and enhance performance in program comprehension activities for blind programmers. This paper reports the results of a study into creating a better fisheye view of java source code, by improving the method used to determine each line's 'global importance' or 'Level of Detail' (LOD). The traditional LOD determination method uses only the indentation level of a line to calculate its overall importance. This paper describes the results of the study, and suggests some of the issues which may need to be considered in developing an improved LOD calculation for programming source code.
java has become a popular paradigm in software development. It is widely used in embedded systems and network computing because of its excellent robustness, modularity and security. Its built-in garbage collection aut...
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ISBN:
(纸本)9780769527840
java has become a popular paradigm in software development. It is widely used in embedded systems and network computing because of its excellent robustness, modularity and security. Its built-in garbage collection automatically reclaims unused memory space. Current generational garbage collector works well with programs containing massive short-lived objects. However, the existence of hot-mature (i.e. frequently-accessed and long-lived) objects inhibits object reclamation. In this paper, we present two methodologies to exploit the locality for these objects. Firstly, we employ an on-chip scratchpad memory in memory hierarchy to preserve young and hot-mature objects. This reduces energy consumption and data accessing cycles for java execution. Secondly, we introduce a pretenuring technique to segregate objects into separated memory regions based on the object lifetimes and reference densities, which minimizes the amount of object copying during garbage collections.
Non-interference is a semantical condition on programs that guarantees the absence of illicit information flow throughout their execution, and that can be enforced by appropriate information flow type systems. Much of...
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ISBN:
(纸本)9783540713142
Non-interference is a semantical condition on programs that guarantees the absence of illicit information flow throughout their execution, and that can be enforced by appropriate information flow type systems. Much of previous work on type systems for non-interference has focused on calculi or high-level programminglanguages, and existing type systems for low-level languages typically omit objects, exceptions, and method calls, and/or do not prove formally the soundness of the type system. We define an information flow type system for a sequential JVM-like language that includes classes, objects, arrays, exceptions and method calls, and prove that it guarantees non-interference. For increased confidence, we have formalized the proof in the proof assistant Coq, an additional benefit of the formalization is that we have extracted from our proof a certified lightweight bytecode verifier for information flow. Our work provides, to our best knowledge, the first sound and implemented information flow type system for such an expressive fragment of the JVM.
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