/**
         * Method toString.
         *
         * @param location
         * @return String
         */
        public abstract String toString(InputLocation location);
    }

    @Override
    public String toString() {
        return getLineNumber() + " : " + getColumnNumber() + ", " + getSource();
    }

  enum ExampleFeature implements Feature<Object> {
    FOO,
    IMPLIES_FOO,
    IMPLIES_IMPLIES_FOO,
    BAR,
    IMPLIES_BAR,
    IMPLIES_IMPLIES_FOO_AND_IMPLIES_BAR;

    @Override
    public ImmutableSet<Feature<? super Object>> getImpliedFeatures() {
      switch (this) {
        case IMPLIES_FOO:
          return ImmutableSet.of(FOO);
        case IMPLIES_IMPLIES_FOO:

    },
    {Long.MAX_VALUE, 2, 325, 9375, 28178, 450775, 9780504, 1795265022}
  };

  private enum MillerRabinTester {
    /** Works for inputs ≤ FLOOR_SQRT_MAX_LONG. */
    SMALL {
      @Override
      long mulMod(long a, long b, long m) {
        /*
         * lowasser, 2015-Feb-12: Benchmarks suggest that changing this to UnsignedLongs.remainder

    //                                                                       Name Override
    //                                                                       =============
    @Override
    public String asTableDbName() {
        return "elevate_word";
    }

    @Override
    public String xgetAliasName() {
        return "elevate_word";
    }

    //                                                                       Name Override
    //                                                                       =============
    @Override
    public String asTableDbName() {
        return "click_log";
    }

    @Override
    public String xgetAliasName() {
        return "click_log";
    }

      return Unsafe.getUnsafe();
    } catch (SecurityException tryReflectionInstead) {
    }
    try {
      return AccessController.doPrivileged(
          new PrivilegedExceptionAction<Unsafe>() {
            @Override
            public Unsafe run() throws Exception {
              Class<Unsafe> k = Unsafe.class;
              for (Field f : k.getDeclaredFields()) {
                f.setAccessible(true);

     */
    FAILED,
  }

  /**
   * A listener for the various state changes that a {@link Service} goes through in its lifecycle.
   *
   * <p>All methods are no-ops by default, implementors should override the ones they care about.
   *
   * @author Luke Sandberg
   * @since 15.0 (present as an interface in 13.0)
   */
  abstract class Listener {
    /**

    }

    @Override
    public Iterable<? extends Character> successors(Character node) {
      requestedNodes.add(node);
      return delegate.successors(node);
    }
  }

  private static <N> SuccessorsFunction<N> fixedSuccessors(final Iterable<N> successors) {
    return new SuccessorsFunction<N>() {
      @Override
      public Iterable<N> successors(N n) {

    }

    @Override
    public Iterable<? extends Character> successors(Character node) {
      requestedNodes.add(node);
      return delegate.successors(node);
    }
  }

  private static <N> SuccessorsFunction<N> fixedSuccessors(final Iterable<N> successors) {
    return new SuccessorsFunction<N>() {
      @Override
      public Iterable<N> successors(N n) {

    val firstConnectLatch = CountDownLatch(1)
    val socketFactory =
      object : DelegatingSocketFactory(SocketFactory.getDefault()) {
        var first = true

        override fun createSocket(): Socket {
          if (first) {
            first = false
            firstConnectLatch.await()
          }
          return super.createSocket()
        }
      }

    client =