import java.util.concurrent.TimeUnit;
import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.BenchmarkMode;
import org.openjdk.jmh.annotations.Fork;
import org.openjdk.jmh.annotations.Measurement;
import org.openjdk.jmh.annotations.Mode;
import org.openjdk.jmh.annotations.OutputTimeUnit;
import org.openjdk.jmh.annotations.Scope;
import org.openjdk.jmh.annotations.State;
import org.openjdk.jmh.annotations.Warmup;
import org.openjdk.jmh.infra.Blackhole;
import org.openjdk.jmh.runner.Runner;
import org.openjdk.jmh.runner.RunnerException;
import org.openjdk.jmh.runner.options.Options;
import org.openjdk.jmh.runner.options.OptionsBuilder;


@Warmup(iterations = 3)
@Measurement(iterations = 10)
@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.NANOSECONDS)
@State(Scope.Benchmark)
@Fork(2)
public class SumLine {

    private static final String digits = "12345";

    @Benchmark
    public void testSumm(Blackhole bh) {
        bh.consume(summ());

    }

    @Benchmark
    public void testStream(Blackhole bh) {
        bh.consume(stream());
    }

    public int stream() {
        return digits.chars().sum() - digits.length() * '0';
    }

    public int summ() {
        return (Integer.parseInt(digits.charAt(0) + "") + Integer.parseInt(digits.charAt(digits.length() - 1) + "")) / 2 * digits.length();
    }

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

        new Runner(opt).run();
    }

}

# JMH 1.12 (released 62 days ago)
# VM version: JDK 1.8.0_91, VM 25.91-b14
# VM invoker: /usr/lib/jvm/java-8-oracle/jre/bin/java
# VM options: <none>
# Warmup: 3 iterations, 1 s each
# Measurement: 10 iterations, 1 s each
# Timeout: 10 min per iteration
# Threads: 1 thread, will synchronize iterations
# Benchmark mode: Average time, time/op
# Benchmark: ru.stoloto.isalnikov.benchmarkfactorial.SumLine.testStream

# Run progress: 0,00% complete, ETA 00:00:26
# Fork: 1 of 1
# Warmup Iteration   1: 106,927 ns/op
# Warmup Iteration   2: 65,050 ns/op
# Warmup Iteration   3: 56,056 ns/op
Iteration   1: 56,266 ns/op
Iteration   2: 58,029 ns/op
Iteration   3: 56,948 ns/op
Iteration   4: 57,194 ns/op
Iteration   5: 57,900 ns/op
Iteration   6: 56,262 ns/op
Iteration   7: 58,096 ns/op
Iteration   8: 57,537 ns/op
Iteration   9: 56,488 ns/op
Iteration  10: 57,147 ns/op


Result "testStream":
  57,187 ±(99.9%) 1,059 ns/op [Average]
  (min, avg, max) = (56,262, 57,187, 58,096), stdev = 0,701
  CI (99.9%): [56,128, 58,246] (assumes normal distribution)


# JMH 1.12 (released 62 days ago)
# VM version: JDK 1.8.0_91, VM 25.91-b14
# VM invoker: /usr/lib/jvm/java-8-oracle/jre/bin/java
# VM options: <none>
# Warmup: 3 iterations, 1 s each
# Measurement: 10 iterations, 1 s each
# Timeout: 10 min per iteration
# Threads: 1 thread, will synchronize iterations
# Benchmark mode: Average time, time/op
# Benchmark: ru.stoloto.isalnikov.benchmarkfactorial.SumLine.testSumm

# Run progress: 50,00% complete, ETA 00:00:13
# Fork: 1 of 1
# Warmup Iteration   1: 25,852 ns/op
# Warmup Iteration   2: 15,484 ns/op
# Warmup Iteration   3: 14,362 ns/op
Iteration   1: 15,342 ns/op
Iteration   2: 14,914 ns/op
Iteration   3: 14,919 ns/op
Iteration   4: 15,600 ns/op
Iteration   5: 19,118 ns/op
Iteration   6: 17,211 ns/op
Iteration   7: 16,483 ns/op
Iteration   8: 14,844 ns/op
Iteration   9: 15,193 ns/op
Iteration  10: 16,306 ns/op


Result "testSumm":
  15,993 ±(99.9%) 2,044 ns/op [Average]
  (min, avg, max) = (14,844, 15,993, 19,118), stdev = 1,352
  CI (99.9%): [13,950, 18,037] (assumes normal distribution)


# Run complete. Total time: 00:00:27

Benchmark           Mode  Cnt   Score   Error  Units
SumLine.testStream  avgt   10  57,187 ± 1,059  ns/op
SumLine.testSumm    avgt   10  15,993 ± 2,044  ns/op
------------------------------------------------------------------------
BUILD SUCCESS
------------------------------------------------------------------------
Total time: 28.283s
Finished at: Thu Jun 02 18:09:10 MSK 2016
Final Memory: 5M/117M

   @Benchmark
    public void testStream2(Blackhole bh) {
        bh.consume(stream2());
    }

  public int stream2() {
        return digits.chars().map(i -> i - '0').sum();
    }