import java.time.Duration;
import java.util.concurrent.Executor;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;

/**
 * An object with an operational state, plus asynchronous {@link #startAsync()} and {@link
 * #stopAsync()} lifecycle methods to transition between states. Example services include
 * webservers, RPC servers and timers.
 *
 * <p>The normal lifecycle of a service is:
 *
 * <ul>

   */
  private volatile StateSnapshot snapshot = new StateSnapshot(NEW);

  /** Constructor for use by subclasses. */
  protected AbstractService() {}

  /**
   * This method is called by {@link #startAsync} to initiate service startup. The invocation of
   * this method should cause a call to {@link #notifyStarted()}, either during this method's run,

import java.util.concurrent.Executor;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;

/**
 * An object with an operational state, plus asynchronous {@link #startAsync()} and {@link
 * #stopAsync()} lifecycle methods to transition between states. Example services include
 * webservers, RPC servers and timers.
 *
 * <p>The normal lifecycle of a service is:
 *
 * <ul>

  @Override
  public final Throwable failureCause() {
    return delegate.failureCause();
  }

  /** @since 15.0 */
  @CanIgnoreReturnValue
  @Override
  public final Service startAsync() {
    delegate.startAsync();
    return this;
  }

  /** @since 15.0 */
  @CanIgnoreReturnValue
  @Override
  public final Service stopAsync() {
    delegate.stopAsync();
    return this;
  }

  @Override
  public final Throwable failureCause() {
    return delegate.failureCause();
  }

  /** @since 15.0 */
  @CanIgnoreReturnValue
  @Override
  public final Service startAsync() {
    delegate.startAsync();
    return this;
  }

  /** @since 15.0 */
  @CanIgnoreReturnValue
  @Override
  public final Service stopAsync() {
    delegate.stopAsync();
    return this;
  }

  @Override
  public final Throwable failureCause() {
    return delegate.failureCause();
  }

  /** @since 15.0 */
  @CanIgnoreReturnValue
  @Override
  public final Service startAsync() {
    delegate.startAsync();
    return this;
  }

  /** @since 15.0 */
  @CanIgnoreReturnValue
  @Override
  public final Service stopAsync() {
    delegate.stopAsync();
    return this;
  }