string benchmarks

Benchmark                       Mode  Cnt          Score         Error  Units
MyBenchmark.testConcatenation  thrpt   50  336375330.671 ± 2979060.438  ops/s
MyBenchmark.testFormat         thrpt   50    1572940.434 ±   24415.477  ops/s
MyBenchmark.testStringBuilder  thrpt   50   43651155.268 ± 1694489.589  ops/s

import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.infra.Blackhole;

public class MyBenchmark {

    private static final String TO_FORMAT = "This is a %s formatted string";
    private static final String PREFIX = "This is a ";
    private static final String SUFFIX = " formatted string";

    @Benchmark
    public void testFormat(Blackhole bh) {
        bh.consume(String.format(TO_FORMAT, "myString"));
    }

    @Benchmark
    public void testConcatenation(Blackhole bh) {
        bh.consume(PREFIX + "myString" + SUFFIX);
    }

    @Benchmark
    public void testStringBuilder(Blackhole bh) {
        bh.consume(new StringBuilder().append(PREFIX).append("myString").append(SUFFIX).toString());
    }
}