What is GBench?

GBench is a benchmarking framework for Groovy.

Is GBench available on Maven Central?

Yes. So GBench can be installed also via Grape:

@Grab(group='com.googlecode.gbench', module='gbench', version='0.2.2')
import gbench.*

You can check available versions here.

What features does GBench provide?

• Benchmark AST Transformation: An AST Transformation alllows you to benchmark methods without modifying their existing code. See the annotation javadoc for details.
• Example:
• Source code:

import gbench.*

class MyApp {
    @Benchmark
    def aMethod() {
    }
}

• Output:

MyApp  java.lang.Object aMethod()  user:15600100 system:46800300 cpu:62400400 real:396709428

• Benchmark Builder: A Builder allows you to write micro-benchmark code quickly easily, and simply. See the class javadoc for details.
• Example:
• Source code:

import gbench.*

def benchmarker = new BenchmarkBuilder()
def benchmarks = benchmarker.average(repeat: 5, idle: 1) {
    int num = 25
    'recursive fibonacci' {
        { n ->
            if (n < 2) return n
            return call(n - 1) + call(n - 2)
        }(num)
    }
    'iterative fibonacci' {
       { n ->
            int a = 0
            int b = 1
            int c
            for (int i in 2..n) {
                c = a + b
                a = b
                b = c
            }
            return b
        }(num)
    }
}
benchmarks.sort().prettyPrint()

• Output:

                              user        system               cpu            real

iterative fibonacci              0             0                 0          647596
recursive fibonacci     2923458740      18720120        2942178860      2947965327