Stopwatch is a free, simple, highly extensible, Java API that allows developers to easily monitor whole application or any part of it. By default Stopwatch generate reports about hits, execution times (total, average, minimum, maximum) as well as load but it can be easily extended to measure anything else by providing custom engine. Out of the box Stopwatch uses an in-memory HSQL database. It is able to persist collected data using a "storage". There is "storage" provided to persist into HSQL database and custom "storage" can be easily integrated.