Implements a scheme for benchmarking, i.e. for determining and/or reporting the time elapsed between the beginning and the end of an activity.

The measurement is done by invoking begin() and later calling end() whichs returns the time elapsed since the call to begin().

Notice that calls to begin() and end() can be nested, and each call to end() refers to the matching begin() call. To ensure that all calls match, the preferred way to write a benchmark is

...
Benchmark b = new Benchmark();
...
b.begin();
try {
    ....
} finally {
    long ms = b.end();
}

This code layout also makes it visually easy to write correct pairs of begin() / end() pairs.

The pair beginReporting() and endReporting() do basically the same, but report the benchmarking information through an internal Reporter object. The default Reporter prints its messages by System.out.println().

Reporting is only enabled if the Benchmark object was created through Benchmark(boolean) with a true argument.