| Along with the rapid development of the technologies about computer hardware, software and networks, the Internet is of essence in people's everyday life. The way to access Internet by desktop computer does not satisfy with the people's needs for using it anywhere and anyway. And many non-PC Internet accessing devices have emerged, including set-top boxes, wireless phones, and so on.By virtue of its platform independence, Java becomes one of the most popular programming languages in the Internet. And it is the base of many distributed software or standards. Therefore, the ability to support Java program running effectively is requisite to the non-PC Internet accessing devices.The masses of Java virtual machines (JVM) are implemented in software. Their performance is poor. The most important drawback is that they need a large amount of memory. So, it is difficult to use them in these embedded devices with limit resources. In order to solve this problem, it becomes a hot topic to develop the Java chip system, which can support Java program directly.By reason of distinction between the JVM instruction set and the classic ones, there are many problems in architecture, object-orientation implementation, interface between hardware and software, operating system of Java chip system. Existing Java chip systems have many flaws. To overcome these drawbacks, we study the crucial technologies in Java chip system comprehensively in above fields and present JE-Java chip system which is suitable for the non-PC Internet accessing devices. The measurement declares that the performance of JE-Java chip system is close to the similar system. And JE-Java chip is simpler than it.The features of instruction set architecture and application programs are the key factors to microprocessor architecture. By the analysis of JVM instruction set architecture and the measurement of typical Java application programs, the crucial problems to be resolved are ascertained.In order to solve the problems about unfixed instruction length, stack-orientation and addressing virtualization in JVM instruction set, the instruction fetch unit, stack cache and mechanism of address translation in Java chip system are studied. The blueprint of instruction fetch unit is presented and its performance is evaluated with theory model and simulation. And the fetch strategy and parameter are optimized based on above evaluation. Novel stack cache architecture and data-forwarding mechanism between it and the execution unit are also presented. The relationship between the capacity and the backup frequency of the stack cache is analyzed too. Additionally, a new address translation mechanism and related physical memory management algorithm are presented and analyzed, which hybrid the segment and segment-page addressing.Object-oriented instructions are one of the features of JVM instruction set. In accordance with Java specifications, the Java object field model is established and a novel object organization scheme is presented, which can tackle the precise object scan problem in garbage collection. The method dispatch model is also established and two methods to improve the performance of it are presented, including pre-link and object methodreference cache. In order to reduce the overhead of the method context switching, a method context cache in JE-Java chip is presented. The execution of these object-oriented instructions can be accelerated by these technologies.Because of the absence of the direct hardware control instructions in JVM, an object-oriented interface between hardware and software and its implementation are presented. By the interface, an integrated object-oriented overview is provided and drawbacks caused by instruction expansion are avoided.In view of the requirement of Java cfiip operating system (JCOS), a fresh JCOS model and its implementation are presented. This JCOS is different from the classic ones in structure and design method: it is comprised by independent severs, translation layers and kernel, and the common features...
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