CapturingLambda.java

package playground;

import org.openjdk.jmh.annotations.*;

import java.util.concurrent.TimeUnit;
import java.util.function.Supplier;

@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.NANOSECONDS)
@State(Scope.Benchmark)
@Fork(value = 2) //, jvmArgsAppend = "-XX:TieredStopAtLevel=1")
@Measurement(iterations = 5)
@Warmup(iterations = 5)
public class CapturingLambda {

  private Integer param;

  @Setup
  public void setup() throws Exception {
    param = 3;
  }

  @Benchmark
  public Integer returnParam() {
    return param;
  }

  @Benchmark
  public Integer returnViaClosure() {
    return call(() -> param);
  }

  @CompilerControl(CompilerControl.Mode.INLINE)
  public Integer call(Supplier<Integer> supplier) {
    return supplier.get();
  }

}