A simple example of a gradle project with a jmh benchmark

I was curious about if there was a difference between a new Data() and System.currentTimeMillis(), so I wrote a quick and dirty JMH benchmark.

It was really so I could set up a project and get started with JMH benchmarks.

to run

./gradlew jmh

You will get some results like this

Benchmark                     Mode  Cnt         Score         Error  Units
SampleBenchmark.date         thrpt    5  19643682.901 ± 1612197.581  ops/s
SampleBenchmark.instant      thrpt    5   9212400.316 ± 9126592.808  ops/s
SampleBenchmark.miliseconds  thrpt    5  22064363.376 ± 5447924.068  ops/s

if you want to change the iterations, or warmups, you can do so in build.gradle

jmh {
    warmupIterations = 2
    iterations = 5
    fork = 1
}

I don't know how accurate the results are, and this is not a fully worked benchmark.

I welcome changes that make the tests more accurate. I don't welcome criticisms without code to improve the issues. This is just play code.

I wanted to see the computational difference between two bits of java code.

// Date based time taken
return (new Date().getTime() - Start_Date.getTime());

vs

// .currentTimeMillis version
return (System.currentTimeMillis() - startTime);