* <p>In light of the significant enhancements to {@code Comparator} in Java 8, the overwhelming
 * majority of usages of {@code Ordering} can be written using only built-in JDK APIs. This class is
 * intended to "fill the gap" and provide those features of {@code Ordering} not already provided by
 * the JDK.
 *
 * @since 21.0
 * @author Louis Wasserman
 */
@GwtCompatible
public final class Comparators {
  private Comparators() {}

  /**

    private static final int BYTE_ARRAY_BASE_OFFSET;

    /**
     * Returns an Unsafe. Suitable for use in a 3rd party package. Replace with a simple call to
     * Unsafe.getUnsafe when integrating into a JDK.
     *
     * @return an Unsafe instance if successful
     */
    private static Unsafe getUnsafe() {
      try {
        return Unsafe.getUnsafe();
      } catch (SecurityException tryReflectionInstead) {

    if: github.ref == 'refs/heads/master' || contains(github.event.pull_request.labels.*.name, 'documentation')

    steps:
      - name: Checkout
        uses: actions/checkout@v5

      - name: Configure JDK
        uses: actions/setup-java@v5
        with:
          distribution: 'zulu'
          java-version: 17

      - uses: actions/setup-python@v5
        with:
          python-version: 3.x

   * Returns the {@link Method} instance for {@link #testPutAll_nullKeyUnsupported()} so that tests
   * can suppress it with {@code FeatureSpecificTestSuiteBuilder.suppressing()} until <a
   * href="https://bugs.openjdk.org/browse/JDK-5045147">JDK-5045147</a> is fixed.
   */
  @J2ktIncompatible
  @GwtIncompatible // reflection
  public static Method getPutAllNullKeyUnsupportedMethod() {

        }
    }

    private boolean isExceptPrivateAccessible(Method method) {
        // to avoid warning of JDK-internal access at Java11
        // Lasta Di does not need private access to the classes
        final String fqcn = method.getDeclaringClass().getName();
        return fqcn.startsWith("java.") || fqcn.startsWith("jdk.") || fqcn.startsWith("com.sun.") || fqcn.startsWith("sun.");
    }

    @Override

 * <p>This class is tailored toward use cases in common.graph. It is *NOT* a general purpose map.
 *
 * @author James Sexton
 */
class MapIteratorCache<K, V> {
  private final Map<K, V> backingMap;

  /*
   * Per JDK: "the behavior of a map entry is undefined if the backing map has been modified after
   * the entry was returned by the iterator, except through the setValue operation on the map entry"

  @Override
  public @Nullable V replace(K key, V value) {
    return delegate().replace(key, value);
  }

  @CanIgnoreReturnValue
  @Override
  @SuppressWarnings("nullness") // https://github.com/jspecify/jdk/issues/118
  public boolean replace(K key, V oldValue, V newValue) {
    return delegate().replace(key, oldValue, newValue);
  }

        }
        return sb.toString();
      }
    },
    // It really seems like this should be faster than TO_BYTE_ARRAY_NEW_STRING.  But it just isn't
    // my best guess is that the jdk authors have spent more time optimizing that callpath than this
    // one. (StringCoding$StringDecoder vs. StreamDecoder).  StringCoding has a ton of special cases

    return longBitsToDouble(significand | ONE_BITS);
  }

  static double bigToDouble(BigInteger x) {
    // This is an extremely fast implementation of BigInteger.doubleValue(). JDK patch pending.
    BigInteger absX = x.abs();
    int exponent = absX.bitLength() - 1;
    // exponent == floor(log2(abs(x)))
    if (exponent < Long.SIZE - 1) {
      return x.longValue();

 * introduced in Unicode 3.1. One implication of this is that it rejects <a
 * href="http://www.unicode.org/versions/corrigendum1.html">"non-shortest form"</a> byte sequences,
 * even though the JDK decoder may accept them.
 *
 * @author Martin Buchholz
 * @author Clément Roux
 * @since 16.0
 */
@GwtCompatible
public final class Utf8 {
  /**