Java – how to write a small benchmark for GetBytes in jmh?

I'm new to jmh and benchmarking I have written a small test of the public byte [] GetBytes (string charsetname) method However, Maven cannot be established This is my code:

package org.openjdk.jmh.samples;
@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.NANOSECONDS)
@State(Scope.Thread)

public class Test
{   @GenerateMicroBenchmark
   public byte [] testgetbyte (String Str)
   {   

   byte[] bytes = Str.getBytes("ISO-8859-1");
   return bytes;
    }

public static void main(String[] args) throws RunnerException {      
    Options opt = new OptionsBuilder()
            .include(Test.class.getSimpleName())
            .warmupIterations(5)
            .measurementIterations(5)
            .forks(1)
            .build();

    new Runner(opt).run();

}

    }

When I run: MVN clean install I received a build failure error message

Solution

@Generatemicrobenchmark seems to indicate that you are using an old version of jmh. Please update it Using jmh 1.7, this example:

@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.NANOSECONDS)
@State(Scope.Thread)
public class Test {
    @Benchmark
    public byte[] test(String str) throws UnsupportedEncodingException {
        return str.getBytes("ISO-8859-1");
    }
}

... said:

[ERROR] /home/shade/temp/stest/src/main/java/org/openjdk/Test.java:
[19,19] Method parameters should be @State classes.

This just shows that string STR is an unacceptable @ benchmark parameter Think about it: what string should jmh use to call this method? Who will produce it? What does it contain? These answers should be provided by the user through the @ state class, such as jmhsample_ 03_ States and jmhsample_ 04_ As described in defaultstate