import static java.lang.Character.MAX_SURROGATE;
import static java.lang.Character.MIN_SURROGATE;

import com.google.common.annotations.GwtCompatible;

/**
 * Low-level, high-performance utility methods related to the {@linkplain Charsets#UTF_8 UTF-8}
 * character encoding. UTF-8 is defined in section D92 of <a
 * href="http://www.unicode.org/versions/Unicode6.2.0/ch03.pdf">The Unicode Standard Core

   *
   * <p><b>Performance note:</b> When feasible, {@code initialCapacity} should be the exact number
   * of values that will be added, if that knowledge is readily available. It is better to guess a
   * value slightly too high than slightly too low. If the value is not exact, the {@link
   * ImmutableDoubleArray} that is built will very likely occupy more memory than strictly
   * necessary; to trim memory usage, build using {@code builder.build().trimmed()}.

    CompactLinkedHashSet<E> set = createWithExpectedSize(elements.length);
    Collections.addAll(set, elements);
    return set;
  }

  /**
   * Creates a {@code CompactLinkedHashSet} instance, with a high enough "initial capacity" that it
   * <i>should</i> hold {@code expectedSize} elements without rebuilding internal data structures.
   *
   * @param expectedSize the number of elements you expect to add to the returned set

     * wrapper around j.u.HashSet, which has built-in flooding protection. MAX_RUN_MULTIPLIER was
     * determined experimentally to match our desired probability of false positives.
     */
    // NB: yes, this is surprisingly high, but that's what the experiments said was necessary
    // Raising this number slows the worst-case contains behavior, speeds up hashFloodingDetected,
    // and reduces the false-positive probability.

   * having a hash table of size eight. Providing a large enough estimate at construction time
   * avoids the need for expensive resizing operations later, but setting this value unnecessarily
   * high wastes memory.
   *
   * @throws IllegalArgumentException if {@code initialCapacity} is negative
   * @throws IllegalStateException if an initial capacity was already set
   */
  @CanIgnoreReturnValue

      assertFalse(segment.isLocked());
      Map<?, ?> table = segmentTable(segment);
      // cleanup and then check count after we have a strong reference to all entries
      segment.cleanUp();
      // under high memory pressure keys/values may be nulled out but not yet enqueued
      assertThat(table.size()).isAtMost(segment.count);
      for (Entry<?, ?> entry : table.entrySet()) {
        assertNotNull(entry.getKey());

    if (isTeredoAddress(ip)) {
      return false;
    }

    byte[] bytes = ip.getAddress();

    if ((bytes[8] | (byte) 0x03) != (byte) 0x03) {

      // Verify that high byte of the 64 bit identifier is zero, modulo
      // the U/L and G bits, with which we are not concerned.
      return false;
    }

      assertFalse(segment.isLocked());
      Map<?, ?> table = segmentTable(segment);
      // cleanup and then check count after we have a strong reference to all entries
      segment.cleanUp();
      // under high memory pressure keys/values may be nulled out but not yet enqueued
      assertThat(table.size()).isAtMost(segment.count);
      for (Entry<?, ?> entry : table.entrySet()) {
        assertNotNull(entry.getKey());

  public static <K extends @Nullable Object, V extends @Nullable Object>
      CompactHashMap<K, V> create() {
    return new CompactHashMap<>();
  }

  /**
   * Creates a {@code CompactHashMap} instance, with a high enough "initial capacity" that it
   * <i>should</i> hold {@code expectedSize} elements without growth.
   *
   * @param expectedSize the number of elements you expect to add to the returned set

   * resizing.
   *
   * @throws IllegalArgumentException if {@code size} is negative
   */
  public static ByteArrayDataOutput newDataOutput(int size) {
    // When called at high frequency, boxing size generates too much garbage,
    // so avoid doing that if we can.
    if (size < 0) {
      throw new IllegalArgumentException(String.format("Invalid size: %s", size));
    }