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Java Processor Optimized for RTSJ


Due to the preeminent work of the real-time specification for Java (RTSJ), Java is increasingly expected to become the leading programming language in real-time systems. To provide a Java platform suitable for real-time applications, a Java processor which can execute Java bytecode is directly proposed in this paper. It provides efficient support in hardware for some mechanisms specified in the RTSJ and offers a simpler programming model through ameliorating the scoped memory of the RTSJ. The worst case execution time (WCET) of the bytecodes implemented in this processor is predictable by employing the optimization method proposed in our previous work, in which all the processing interfering predictability is handled before bytecode execution. Further advantage of this method is to make the implementation of the processor simpler and suited to a low-cost FPGA chip.

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Correspondence to Zhilei Chai.

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Open Access This article is distributed under the terms of the Creative Commons Attribution 2.0 International License (, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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Chai, Z., Xu, W., Tu, S. et al. Java Processor Optimized for RTSJ. J Embedded Systems 2007, 057575 (2007).

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