Japex is a simple yet powerful tool to write Java-based micro-benchmarks. It is similar in spirit to JUni] in that if factors out most of the repetitive programming logic that is necessary to write in micro-benchmarks. This logic includes loading and initializing multiple drivers, warming up the VM, timing the inner loop, etc.
The input to Japex is an XML file describing a test suite. The output is a timestamped report available in both XML and HTML formats (although generation of the latter can be turned off). HTML reports include one or more bar charts generated using JFreeChart which graphically display the data for ease of comparison.