final List<String> events = Lists.newArrayList();

    @Override
    public long readMicros() {
      return NANOSECONDS.toMicros(instant);
    }

    void sleepMillis(int millis) {
      sleepMicros("U", MILLISECONDS.toMicros(millis));
    }

    void sleepMicros(String caption, long micros) {
      instant += MICROSECONDS.toNanos(micros);

 * {@link PairedStatsAccumulator#snapshot} method which returns {@link PairedStats} instances, see
 * {@link PairedStatsTest}.
 *
 * @author Pete Gillin
 */
public class PairedStatsAccumulatorTest extends TestCase {

  private PairedStatsAccumulator emptyAccumulator;
  private PairedStatsAccumulator emptyAccumulatorByAddAllEmptyPairedStats;

/**
 * An immutable value object capturing some basic statistics about a collection of paired double
 * values (e.g. points on a plane). Build instances with {@link PairedStatsAccumulator#snapshot}.
 *
 * @author Pete Gillin
 * @since 20.0
 */
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault
public final class PairedStats implements Serializable {

  private final Stats xStats;
  private final Stats yStats;

 * {@link PairedStatsAccumulator#snapshot} method which returns {@link PairedStats} instances, see
 * {@link PairedStatsTest}.
 *
 * @author Pete Gillin
 */
public class PairedStatsAccumulatorTest extends TestCase {

  private PairedStatsAccumulator emptyAccumulator;
  private PairedStatsAccumulator emptyAccumulatorByAddAllEmptyPairedStats;

    ImmutableMap<Service, Long> startupTimes = serviceManager.startupTimes();
    assertThat(startupTimes).hasSize(2);
    assertThat(startupTimes.get(a)).isAtLeast(150);
    // Service b startup takes at least 353 millis, but starting the timer is delayed by at least
    // 150 milliseconds. so in a perfect world the timing would be 353-150=203ms, but since either

    }
  }

  private static void assertNotInterrupted() {
    assertFalse(Thread.interrupted());
  }

  private static void requestInterruptIn(long millis) {
    InterruptionUtil.requestInterruptIn(millis, MILLISECONDS);
  }

  @CanIgnoreReturnValue
  private static Thread acquireFor(final Lock lock, final long duration, final TimeUnit unit) {

 * transformation in which case {@code x} has a constant value for all {@code y}. In the
 * non-vertical case, {@code m} is the slope of the transformation (and a horizontal transformation
 * has zero slope).
 *
 * @author Pete Gillin
 * @since 20.0
 */
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault
public abstract class LinearTransformation {

  /**

import java.util.List;

/**
 * Inputs, expected outputs, and helper methods for tests of {@link StatsAccumulator}, {@link
 * Stats}, {@link PairedStatsAccumulator}, and {@link PairedStats}.
 *
 * @author Pete Gillin
 */
class StatsTesting {
  // TODO(cpovirk): Convince myself that this larger error makes sense.
  static final double ALLOWED_ERROR = isAndroid() ? .25 : 1e-10;

  // Inputs and their statistics:

    }
  }

  private static void assertNotInterrupted() {
    assertFalse(Thread.interrupted());
  }

  private static void requestInterruptIn(long millis) {
    InterruptionUtil.requestInterruptIn(millis, MILLISECONDS);
  }

  @CanIgnoreReturnValue
  private static Thread acquireFor(final Lock lock, final long duration, final TimeUnit unit) {

 *
 * <p>Basic usage:
 *
 * <pre>{@code
 * Stopwatch stopwatch = Stopwatch.createStarted();
 * doSomething();
 * stopwatch.stop(); // optional
 *
 * long millis = stopwatch.elapsed(MILLISECONDS);
 *
 * log.info("time: " + stopwatch); // formatted string like "12.3 ms"
 * }</pre>
 *
 * <p>The state-changing methods are not idempotent; it is an error to start or stop a stopwatch