The development of a complete Java Virtual Machine (JVM) implementation is a tedious process which involves knowledge in different areas: garbage collection, just in time compilation, interpretation, file parsing, data structures, etc. The result is that developing its own virtual machine requires a considerable amount of man/year. In this paper we show that one can implement a JVM with third party software and with performance comparable to industrial and top open-source JVMs on scientific applications. Our proof-of-concept implementation uses existing versions of a garbage collector, a just in time compiler, and the base library, and is robust enough to execute complex Java applications such as the OSGi Felix implementation and the Tomcat servlet container.