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Robert St¨ark, Joachim Schmid, Egon B¨orger Java and the Java Virtual Machine Definition, Verification, Validation May 8, 2001 Springer-Verlag Berlin Heidelberg NewYork London Paris Tokyo Hong Kong Barcelona Budapest Preface The origin of this book goes back to the Dagstuhl seminar on Logic for System Engineering, organized during the first week of March 1997 by S. J¨ahnichen, J. Loeckx, and M. Wirsing. During that seminar, after Egon B¨orger’s talk on How to Use Abstract State Machines in Software Engineering, Wolfram Schulte, at the time a research assistant at the University of Ulm, Germany, questioned whether ASMs provide anything special as a scientifically wellfounded and rigorous yet simple and industrially viable framework for highlevel design and analysis of complex systems, and for natural refinements of models to executable code. Wolfram Schulte argued, referring to his work with K. Achatz on A Formal Object-Oriented Method Inspired by Fusion and Object-Z [1], that with current techniques of functional programming and of axiomatic specification, one can achieve the same result. An intensive and long debate arose from this discussion. At the end of the week, it led Egon B¨orger to propose a collaboration on a real-life specification project of Wolfram Schulte’s choice, as a comparative field test of purely functionaldeclarative methods and of their enhancement within an integrated abstract state-based operational (ASM) approach. After some hesitation, in May 1997 Wolfram Schulte accepted the offer and chose as the theme a high-level specification of Java and of the Java Virtual Machine. What followed were two years of hard but enjoyable joint work, resulting in a series of ASM models of the Java language, of the JVM, and of a provably correct compilation scheme for compiling Java programs to JVM code, which were published in [9, 8, 10, 11, 12]. When in