*/
  static void checkAvalanche(HashFunction function, int trials, double epsilon) {
    Random rand = new Random(0);
    int keyBits = 32;
    int hashBits = function.bits();
    for (int i = 0; i < keyBits; i++) {
      int[] same = new int[hashBits];
      int[] diff = new int[hashBits];
      // go through trials to compute probability
      for (int j = 0; j < trials; j++) {
        int key1 = rand.nextInt();

    utf8Lengths.put(MAX_CODE_POINT, 4);

    Integer[] codePoints = utf8Lengths.keySet().toArray(new Integer[] {});
    StringBuilder sb = new StringBuilder();
    Random rnd = new Random();
    for (int trial = 0; trial < 100; trial++) {
      sb.setLength(0);
      int utf8Length = 0;
      for (int i = 0; i < 6; i++) {
        Integer randomCodePoint = codePoints[rnd.nextInt(codePoints.length)];

    Random random = new Random();
    int warmupPermits = 10;
    double[] coldFactorsToTest = {2.0, 3.0, 10.0};
    double[] qpsToTest = {4.0, 2.0, 1.0, 0.5, 0.1};
    for (int trial = 0; trial < 100; trial++) {
      for (double coldFactor : coldFactorsToTest) {
        for (double qps : qpsToTest) {
          // If warmupPermits = maxPermits - thresholdPermits then

    Random random = new Random();
    int warmupPermits = 10;
    double[] coldFactorsToTest = {2.0, 3.0, 10.0};
    double[] qpsToTest = {4.0, 2.0, 1.0, 0.5, 0.1};
    for (int trial = 0; trial < 100; trial++) {
      for (double coldFactor : coldFactorsToTest) {
        for (double qps : qpsToTest) {
          // If warmupPermits = maxPermits - thresholdPermits then

    boolean interrupted = false;
    try {
      long remainingNanos = unit.toNanos(timeout);
      long end = System.nanoTime() + remainingNanos;

      while (true) {
        try {
          // CountDownLatch treats negative timeouts just like zero.
          return latch.await(remainingNanos, NANOSECONDS);
        } catch (InterruptedException e) {
          interrupted = true;
          remainingNanos = end - System.nanoTime();

    try {
      long remainingNanos = unit.toNanos(timeout);
      long end = System.nanoTime() + remainingNanos;

      while (true) {
        try {
          // TimeUnit.timedJoin() treats negative timeouts just like zero.
          NANOSECONDS.timedJoin(thread, remainingNanos);
          return;
        } catch (InterruptedException e) {
          interrupted = true;

    try {
      long remainingNanos = unit.toNanos(timeout);
      long end = System.nanoTime() + remainingNanos;

      while (true) {
        try {
          // TimeUnit.timedJoin() treats negative timeouts just like zero.
          NANOSECONDS.timedJoin(thread, remainingNanos);
          return;
        } catch (InterruptedException e) {
          interrupted = true;

   * compares, using {@link #compare(float, float)}), the first pair of values that follow any
   * common prefix, or when one array is a prefix of the other, treats the shorter array as the
   * lesser. For example, {@code [] < [1.0f] < [1.0f, 2.0f] < [2.0f]}.
   *
   * <p>The returned comparator is inconsistent with {@link Object#equals(Object)} (since arrays

   * compares, using {@link #compare(double, double)}), the first pair of values that follow any
   * common prefix, or when one array is a prefix of the other, treats the shorter array as the
   * lesser. For example, {@code [] < [1.0] < [1.0, 2.0] < [2.0]}.
   *
   * <p>The returned comparator is inconsistent with {@link Object#equals(Object)} (since arrays

   * on {@link Platform} so that we can have different behavior in GWT.
   *
   * <p>This implementation tries to be smart in a number of ways. It recognizes cases where the
   * negation is cheaper to precompute than the matcher itself; it tries to build small hash tables
   * for matchers that only match a few characters, and so on. In the worst-case scenario, it