• Proceedings of the Korean Information Science Society Conference
• /
• 2002.10c
• /
• pp.484-486
• /
• 2002

이 논문에서는 자바 카드를 위한 통합 테스트 및 디버깅 환경에 대해 기술하고 있으며, 제안한 통합 개발 환경은 J-JCRE (Java language based Java Card Runtime Environment) 와 Java Card API (Application Programming Interface)로 구성되어 있다. 또한, 개발 환경은 현재 두 가지 암호 알고리즘을 지원해주며, 스크립트 실행, 시스템 클래스의 소스 레벨 디버깅, 클라이언트/서버 skeleton 자동 생성 등 다양한 기능을 제공해 준다. 제안한 통합 개발 환경을 이용함으로써 사용자들은 실제 자바 카드에 응용 프로그램을 탑재하기 전에 응용 프로그램 테스트 및 디버깅을 통해 프로그램상의 오류 밀 에러를 미리 점검하여 수정할 수 있게 된다.

• The KIPS Transactions:PartA
• /
• v.11A no.5
• /
• pp.319-324
• /
• 2004

The Java language is rapidly being adopted in the Internet. The distributed applications and their application range are being expanded beyond just a programing language and developed Into software applications. A variety of researches are going on with regard to the Java Virtual Machine runtime environment and methods of analyzing the Java class files and utilizing the information for applications. A class file is a converted file that is executable by the Java virtual machine. Analysis on the class file structure and the runtime processes will be convenient in arranging the decompilers and debugging the source programs. This paper is about the runtime process analyzer that presents the runtime processes, including class files, more visually. The content of a class file will be easily accessed and expressed as in a graphic user interface. The information in the class file displayed is divided into Constant_Pool, Class_file, Interface, Field, Method and Attribute with information on method area, operand stack and local variables expressed visually.

• Proceedings of the Korean Information Science Society Conference
• /
• 2006.10a
• /
• pp.309-312
• /
• 2006

현재의 네트워크화 된 환경에서 Reverse Engineering 방지의 중요성은 높아지고 있다. 특히 Java의 경우 Reverse Engineering에 의한 위험성에 더욱 노출되어 있다. 본 논문에서는 이러한 환경에서 Reverse Engineering 방지에 대한 기존의 연구에 대하여 검토하고, Java 바이트 코드의 암호화를 통한 방어 기법으로서 동적 인스트루멘테이션을 이용한 재구성이 가능한 새로운 Java 실행 환경을 제안하였다. 이를 통하여 보다 신뢰성 있는 모바일 에이전트 환경을 구축할 수 있을 것이다.

• The KIPS Transactions:PartA
• /
• v.8A no.4
• /
• pp.399-410
• /
• 2001

We developed a Java library Xeni for e-book reader systems on embedded Linux environment. Xeni is an API library providing functions such as rendering for XML-based e-book contents, navigation mechanism for readers and bookmark management. This library is developed in Java language, targeting java virtual machines on embedded Linux systems. We discuss design and structure of the developed library, and introduce the reference implementation of a reader system using this library. Also, virtual machines on Linux environment are briefly surveyed.

• Proceedings of the Korean Information Science Society Conference
• /
• 1998.10b
• /
• pp.416-418
• /
• 1998

이기종간의 실행 환경에 적합하도록 설계된 자바 바이트코드는 각 플랫폼에서 인터프리터 방식으로 수행되므로 효율성에서 단점을 가지고 있다. 따라서 바이트코드의 효율적인 실행을 위해 목적 코드로의 변환 과정이 요구된다. 목적 코드로 변환 과정에서 자바의 실행 환경 또한 목적 기계의 실행 환경으로 이전이 이루어져야 한다. 본 논문에서는 자바 실행 환경을 SPARC 실행 환경으로 이전하는 방법을 제시한다. 먼저, 자바 가상 기계의 구성 요소를 분석한 후 이에 대응하는 SPARC 실행 환경에 필요한 각각의 구성 요소들을 제시하고, SPARC 실행 환경에 맞는 모델을 구축한다. 마지막으로, 자바에서 제공하는 표준 클래스 라이브러리에 대해서는 SPARC 라이브러리 형태로 변환하여 제공하게 된다.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.7 no.4
• /
• pp.788-797
• /
• 2003

Class library is one of the most crucial element of Java runtime environment in addition to Java virtual machine. In particular, embedded Java system depends heavily on the class library due to having a low bandwidth communication link and a small amount of memory which are a common restriction of embedded system. It is therefore quite necessary to find the characteristic of the class library for embedded Java system to build an efficient Java runtime environment. In this paper we have analyzed the characteristic of the class library for embedded system. The analysis includes sorts of classes in the library, typical size of the file which contains the class, and the composition of constant pool which is a major part of the file. We also have found typical number of field and method a class contains, the sizes of stack and local variable array each method requires, and the length of bytecode in the method. The result of this study can be used to estimate the startup time for class loading and the size of memory to create an instance of class which are a mandatory information to design an efficient embedded Java virtual machine.

• The KIPS Transactions:PartA
• /
• v.12A no.3 s.93
• /
• pp.229-234
• /
• 2005

The virtual machine is a programming environment that supports device and platform independence. So far, virtual machines such as JVM and KVM have been used in a variety of environments for the Java language. Some virtual machines similar to them are also being developed and used. This paper Presents the experiences of extracting elements essential for small sized devices such as PDA from Java Class files(*.class) and designing a converted class file(*.rclass) for runtime efficiency by modifying its class file format and developing its translator. In addition, a virtual machine is developed to receive the translated class file entered and output the runtime results.

• Journal of Computing Science and Engineering
• /
• v.6 no.2
• /
• pp.105-118
• /
• 2012

We propose two new approaches that automatically parallelize Java programs at runtime. These approaches, which rely on run-time trace information collected during program execution, dynamically recompile Java byte code that can be executed in parallel. One approach utilizes trace information to improve traditional loop parallelization, and the other parallelizes traces instead of loop iterations. We also describe a cost/benefit model that makes intelligent parallelization decisions, as well as a parallel execution environment to execute parallelized programs. These techniques are based on Jikes RVM. Our approach is evaluated by parallelizing sequential Java programs, and its performance is compared to that of the manually parallelized code. According to the experimental results, our approach has low overheads and achieves competitive speedups compared to the manually parallelizing code. Moreover, trace parallelization can exploit parallelism beyond loop iterations.

• Journal of the Korean Society of Systems Engineering
• /
• v.15 no.2
• /
• pp.66-71
• /
• 2019

In digital pathology, an electronic system in the biomedical domain storage of the files is a big constrain and because all the analysis and annotation takes place at every user-end manually, it becomes even harder to manage the data that is being shared inside an enterprise. Therefore, we need such a storage system which is not only big enough to store all the data but also manage it and making communication of that data much easier without losing its true from. A virtual server setup is one of those techniques which can solve this issue. We set a main server which is the main storage for all the virtual machines(that are being used at user-end) and that main server is controlled through a hypervisor so that if we want to make changes in storage overall or the main server in itself, it could be reached remotely from anywhere by just using the server's IP address. The server in our case includes XML-RPC based API which are transmitted between computers using HTTP protocol. JAVA API connects to HTTP/HTTPS protocol through JAVA Runtime Environment and exists on top of other SDK web services for the productivity boost of the running application. To manage the server easily, we use Tkinter library to develop the GUI and pmw magawidgets library which is also utilized through Tkinter. For managing, monitoring and performing operations on virtual machines, we use Python binding to XML-RPC based API. After all these settings, we approach to make the system user friendly by making GUI of the main server. Using that GUI, user can perform administrative functions like restart, suspend or resume a virtual machine. They can also logon to the slave host of the pool in case of emergency and if needed, they can also filter virtual machine by the host. Network monitoring can be performed on multiple virtual machines at same time in order to detect any loss of network connectivity.

• The KIPS Transactions:PartD
• /
• v.10D no.6
• /
• pp.1017-1024
• /
• 2003

Jini is a promising HomeNetworking middleware of computing environment based on Java Technology. To support Homenetwork service based on Jini, Jini device requires a successive operation and complicated management. In this paper, our service management system is a service provider component and lookup service component including automation module. Our automatin module privide searching and setting function of a library, runtime environment and class file system cinfiguration information for Jini service. Our system can be accomplished by automation of runtime environment, simplification of service management structure, visualization of service execution.