Using the jamaicavm command

The command jamaicavm provides a stand-alone version of the Jamaica virtual machine. It can be used directly to quickly execute a Java application. It is the equivalent to the java command that is used to run Java applications with SUN's JDK. A more detailed description of the jamaicavm and similar commands that are part of Jamaica will be given in Chapter 5.

The jamaicavm first loads all class files that are required to start the application. It contains the Jamaica Java interpreter, which then executes the byte code commands found in these class files. Any new class that is referenced by a byte code instruction that is executed will be loaded on demand to execute the full application.

Applications running using the jamaicavm command are not very well optimized. There is no compiler that speeds up execution and no specific measures to reduce footprint are taken. We therefore recommend using the Jamaica builder presented in the next section and in Chapter 6 to run Java applications with JamaicaVM on an embedded system.