*
   * @since 15.0
   */
  public static Stopwatch createStarted() {
    return new Stopwatch().start();
  }

  /**
   * Creates (and starts) a new stopwatch, using the specified time source.
   *
   * @since 15.0
   */
  public static Stopwatch createStarted(Ticker ticker) {
    return new Stopwatch(ticker).start();
  }

  Stopwatch() {

   *
   * @since 15.0
   */
  public static Stopwatch createStarted() {
    return new Stopwatch().start();
  }

  /**
   * Creates (and starts) a new stopwatch, using the specified time source.
   *
   * @since 15.0
   */
  public static Stopwatch createStarted(Ticker ticker) {
    return new Stopwatch(ticker).start();
  }

  Stopwatch() {

    Stopwatch stopwatch = Stopwatch.createStarted();

    assertThrows(UncheckedTimeoutException.class, proxy::sleepThenThrowException);

    assertThat(stopwatch.elapsed(MILLISECONDS)).isIn(Range.closed(NOT_ENOUGH_MS, DELAY_MS * 2));
  }

  public void testCallWithTimeout_goodCallableWithEnoughTime() throws Exception {
    Stopwatch stopwatch = Stopwatch.createStarted();

    Stopwatch stopwatch = Stopwatch.createStarted();

    assertThrows(UncheckedTimeoutException.class, proxy::sleepThenThrowException);

    assertThat(stopwatch.elapsed(MILLISECONDS)).isIn(Range.closed(NOT_ENOUGH_MS, DELAY_MS * 2));
  }

  public void testCallWithTimeout_goodCallableWithEnoughTime() throws Exception {
    Stopwatch stopwatch = Stopwatch.createStarted();

 * @author Kevin Bourrillion
 */
@NullUnmarked
public class StopwatchBenchmark {
  @Benchmark
  long stopwatch(int reps) {
    long total = 0;
    for (int i = 0; i < reps; i++) {
      Stopwatch s = Stopwatch.createStarted();
      // here is where you would do something
      total += s.elapsed(NANOSECONDS);
    }
    return total;
  }

  @Benchmark
  long manual(int reps) {
    long total = 0;

 * @author Kevin Bourrillion
 */
@NullUnmarked
public class StopwatchBenchmark {
  @Benchmark
  long stopwatch(int reps) {
    long total = 0;
    for (int i = 0; i < reps; i++) {
      Stopwatch s = Stopwatch.createStarted();
      // here is where you would do something
      total += s.elapsed(NANOSECONDS);
    }
    return total;
  }

  @Benchmark
  long manual(int reps) {
    long total = 0;

  private final FakeTicker ticker = new FakeTicker();
  private final Stopwatch stopwatch = new Stopwatch(ticker);

  public void testCreateStarted() {
    Stopwatch startedStopwatch = Stopwatch.createStarted();
    assertTrue(startedStopwatch.isRunning());
  }

  public void testCreateUnstarted() {
    Stopwatch unstartedStopwatch = Stopwatch.createUnstarted();
    assertFalse(unstartedStopwatch.isRunning());