This paper describes the design and implementation of a novel dynamic binary translation technique specialized for embedded systems. Virtual platforms have been widely used to develop embedded software and dynamic binary translation is essential to boost their speed in simulations. However, unlike application simulation, the code generated for systems simulation is still slow because the simulator must replicate all of the functions of the target hardware. Embedded systems, which focus on providing one or a few functions, utilize only a small portion of the processor's features most of the time. For example, they may use a Memory Management Unit (MMU) in a processor to map physical memory to effective addresses, but they may not need paged memory support as in an OS. We can exploit this to specialize the dynamically translated code for more performance.

In this paper, we describe static analysis techniques for finding bugs in programs using the Java Native Interface (JNI). The JNI is both tedious and error-prone because there are many JNI-specific mistakes that are not caught by a native compiler. This paper is focused on four kinds of common mistakes. First, explicit statements to handle a possible exception need to be inserted after a statement calling a Java method. However, such statements tend to be forgotten. We present a typestate analysis to detect this exception-handling mistake. Second, while the native code can allocate resources in a Java VM, those resources must be manually released, unlike Java. Mistakes in resource management cause leaks and other errors. To detect Java resource errors, we used the typestate analysis also used for detecting general memory errors. Third, if a reference to a Java resource lives across multiple native method invocations, it should be converted into a global reference. However, programmers sometimes forget this rule and, for example, store a local reference in a global variable for later uses. We provide a syntax checker that detects this bad coding practice. Fourth, no JNI function should be called in a critical region. If called there, the current thread might block and cause a deadlock. Misinterpreting the end of the critical region, programmers occasionally break this rule. We present a simple typestate analysis to detect an improper JNI function call in a critical region.

The paper describes the design of a framework for enterprise Web applications that adapts their contents to various types of Web-enabled terminals, such as wearable devices, PDAs, and automobile PCs. Such terminals have different capabilities as regards their processing units, user interaction, and communication. Thus, applications must dynamically adapt their contents to each type of device when they provide service sessions. On the other hand, applications that serve various dynamic contents from databases and transactions need to be connected to back-end systems, namely, business objects designed independently of the Web applications. For reuse and easy development of such adaptive and enterprise systems, the framework should separate three concerns: (1) design of business objects, (2) design of logical Web contents, and (3) design of the content adaptation. The paper reports the author's experience in designing, implementing, and applying a framework to a banking system using small display devices, and discusses the design.