Though realtime Java offers significant advantages over other programming languages for safe programming, the analysis of worst case execution of realtime Java programs is considerably more difficult. The extra complexity can be addressed using a minimal set of parameterized annotations and data flow analysis to provide a standard worst case execution time analysis tool with the additional information necessary to determine the worst case execution time analysis of realtime Java programms. This methodology has the advantage over existing methods in that it is equally applicable to general purpose library code as to application specific implementation code.