ConTest is a tool that exposes and eliminates concurrency-related bugs in parallel and distributed Java programs. ConTest systematically and transparently schedules the execution of program threads such that program scenarios that are likely to contain race conditions, deadlocks, and other intermittent bugs (collectively called synchronization problems) are forced to appear with high frequency. Because bugs are found earlier in the testing process, ConTest dramatically improves the quality of testing and reduces development expense.  ConTest's impact on the testing effort is minimal. Testers can rerun existing test suites without recompilation of the software under test (but with a greater probability of uncovering synchronization problems). ConTest is easy to use and rcan be set up in less than one day, in most cases. This tool has been used successfully on industrial-sized applications (such as IBM WebSphere) and is, in general, a scalable testing solution. ConTest can also be used to measure test coverage, aid in debugging, and detect potential deadlocks.

Features are:

ConTest is activated by adding a “java_agent” argument to your existing test command and specifying in the ConTest preferences file which of your classes should be targeted. When these classes are loaded by your test, ConTest instruments them around places that are likely to be involved in concurrent bugs.  The ConTest run-time engine adds heuristically controlled conditional instructions that force thread switches, thus helping to reveal concurrent bugs. Each existing test can be run many times: ConTest causes different things to happen every time, and new bugs may surface. ConTest also collects run-time information for coverage and debugging.  This process requires Java 5 and above. ConTest can work with Java 1.4 as well, but the process is slightly different; please consult the "readme" file.