In the area of language-based security, programs written in typed high-level languages need to be translated into those written in typed low-level languages. This work is not trivial when type dispatch constructs are ...
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In the area of language-based security, programs written in typed high-level languages need to be translated into those written in typed low-level languages. This work is not trivial when type dispatch constructs are involved and implemented with tag mechanism. This paper proposes a new type that can deal with a special type dispatch construct occurring in the interface invocation of java. A low-level language with this type is able to efficiently implement the interface invocation. This implementation approach is adopted in a Just-In-Time compiler with a typed low-level language as a certifying language.
We implemented a translator from a subset of C to java that guarantees safety. For such translation, we need to emulate C's pointer arithmetics in java. We thus defined java classes to represent C's pointers a...
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We implemented a translator from a subset of C to java that guarantees safety. For such translation, we need to emulate C's pointer arithmetics in java. We thus defined java classes to represent C's pointers and memory blocks. Next, we defined translation rules which use these classes, and implemented a translator following the rules. We also need to translate integers as pointers, because they can be cast to each other in C. However, representing all integers as pointers incurs too much overhead. We therefore implemented optimizations, including a data flow analysis for translating C's integer variables (to which no pointers are assigned) to java's integer variables. We conducted experiments with 9 benchmark programs. Without optimizations, the translated programs were 3.3-585 times slower than the original C programs. After the optimizations, those numbers improved to 1.3-5.9.
Generalization is an important category of refactorings, preconditions of which depend on the type constraints of the program. The existing automatic generalization refactoring methods do not solve the type constraint...
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Generalization is an important category of refactorings, preconditions of which depend on the type constraints of the program. The existing automatic generalization refactoring methods do not solve the type constraints of parameterized type in generic programs, which results in the type-incorrect problem after refactoring. In this paper we present a serial of type inference rules for generic java programs. Type constraints can be solved via traversing a type constraint graph according to the rules. Automatic refactoring algorithms for Extract Interface and Pull Up Members are proposed. The algorithms can preserve type-correctness and run in a linear time with the size of the refactored program.
This article focuses on the simulation of electromagnetic signal propagation over large areas with complex atmospheric and terrain. An electromagnetic signal propagation simulation system was designed using parabolic ...
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This article focuses on the simulation of electromagnetic signal propagation over large areas with complex atmospheric and terrain. An electromagnetic signal propagation simulation system was designed using parabolic equation model and java programming language. The system consists of two parts, the modeling of atmosphere and terrain and the step-by-step calculation part with parabolic equation. The output of this system is the loss value of the calculation area. Given some test input, the results calculated by the system are consistent with the results of AREPS (advanced refractive effects prediction system) developed by the United States. The system is of great significance to electromagnetic environment simulation over the complex battlefield environment and the construction of the nation defense early warning facilities.
In order to discover and control the illegal information flow in programs, the safety of java was augmented with improved military security model (IMSM) and a type-based information control method was proposed. Securi...
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In order to discover and control the illegal information flow in programs, the safety of java was augmented with improved military security model (IMSM) and a type-based information control method was proposed. Security levels were coded as types in source program, and the illegal information flow was caught by typing rules. The security of the augmented javalanguage called sjava was proved. Jikes, a kind of open source java compiler was reconstructed. Results show that the sjava programs can be compiled directly to byte code in reconstructed Jikes without increasing the loads of system.
Based on the three different dimensions of coupling put forward by Eder, we have a detail research for interaction coupling in java using the hierarchical slicing model (HSM), and we get some results which are express...
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Based on the three different dimensions of coupling put forward by Eder, we have a detail research for interaction coupling in java using the hierarchical slicing model (HSM), and we get some results which are expressed by some formulas. In contrast with the coupling metrics before, our HSM-based approach is more precise, not only pointing out the coupling relationships between objects, but also specifying the degrees for coupling, which can provide us with some more useful program related information when we have some software activities, such as program analysis or understanding.
java memory model (JMM) is an important topic in javalanguage and java virtual machine (JVM) design. But the memory model in java specification can't guarantee the safely running of java multithread code. It need...
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java memory model (JMM) is an important topic in javalanguage and java virtual machine (JVM) design. But the memory model in java specification can't guarantee the safely running of java multithread code. It needs memory coherence, which imposes constraints that prohibit JVM implementation optimization. To fix the problem of java memory model in java specification, a new java memory model, L-JMM, is proposed, which is based on location consistency. This model extends the location consistency to adapt the features of java technology. It also defines the rule of java multithread memory operation, including ordinary variable rule, volatile variable rule, final variable rule and synchronization rule. It is proved that this memory model has the same property as location consistency. It can guarantee the correctness for java multithread code. It can also improve the performance of java virtual machine. Finally, the simulation of this memory model in the simulator MMS verifies that the new model boasts a better performance than the java specification memory model does.
This paper describes the design, implementation and application of a multistage fuzzy controller for a coupled tank system, through the OPC industrial protocol. It also presents the details of a fuzzy logic toolbox fo...
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ISBN:
(纸本)9781467303408;9781467303422
This paper describes the design, implementation and application of a multistage fuzzy controller for a coupled tank system, through the OPC industrial protocol. It also presents the details of a fuzzy logic toolbox for industrial process control based on javalanguage, providing easy and functional tools for modelling, building and editing complex fuzzy inference systems and using such logic systems to control a large variety of industrial processes.
Nowadays software developments aim on managed code that organizes the memory occupation itself automatically by using the runtime environment. Hence, this is supposed to be very time intensive but simplifies the imple...
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ISBN:
(纸本)9781424470594
Nowadays software developments aim on managed code that organizes the memory occupation itself automatically by using the runtime environment. Hence, this is supposed to be very time intensive but simplifies the implementation in an immense way. Therefore, java is used to determine the advantages and disadvantages of managed code in numerical simulations. In a first step a 3-D electrostatic FEM formulation is implemented in pure java code by using an object-oriented structure based on design patterns. For an example of a 3-D numerical problem the processing time and the memory occupation are investigated and discussed regarding the use of pure java code.
As an outcome of a DAAD (German Academic Exchange Service) sub-project started in 2004 and devoted to teaching the java programming language, a joint pool of primarily advanced topics has been created. This teaching m...
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As an outcome of a DAAD (German Academic Exchange Service) sub-project started in 2004 and devoted to teaching the java programming language, a joint pool of primarily advanced topics has been created. This teaching material has since been used by teachers from different member universities and countries. In this paper we present recent modifications of the joint pool, with the main goal of innovating and improving its topics. The result of these efforts has been a realization of a completely new, elective object-oriented programming II course.
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