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OEM Software

Classlinker to link Java applications

Preparing applications for the virtual machine
On the wireless sensor node "Preon32" the virtual machine is used as the operating software. This virtual machine makes it possible to run applications written in Java™ on the Preon32 module.

Normally a Java compiler compiles Java sources to Java .class files. A Java Virtual Machine can then load and use these .class files.

The Virtenio VM cannot load and run .class files directly. The class files are too large for Virtenio's target systems. The ClassLinker was developed to overcome this restriction by transforming the .class files into a file format that the Virtenio VM can process. The resulting files are suffixed with .vmm which stands for Virtual Machine Module.

The Virtual Machine Modules (.vmm) only contain information that is essential to the Virtenio VM. Each module consists of the translated information of several .class files. The .vmm files are very small compared to the .class files of which the module was originally made of.

The entire transformation process from Java sources files to .vmm files is illustrated in the figure below.
ClassLinker Transformationsprozess
Figure: Transformation of Java source files to .vmm files in preparation for subsequent interpretation by the Virtenio VM