*
   * <ul>
   *   <li>{@code null} initial state, nothing has happened.
   *   <li>{@link Cancellation} terminal state, {@code cancel} was called.
   *   <li>{@link Failure} terminal state, {@code setException} was called.
   *   <li>{@link DelegatingToFuture} intermediate state, {@code setFuture} was called.
   *   <li>{@link #NULL} terminal state, {@code set(null)} was called.

/**
 * Utility class for conversions related to {@link BigInteger}.
 *
 * @author higa
 */
public abstract class BigIntegerConversionUtil {

    /**
     * Do not instantiate.
     */
    protected BigIntegerConversionUtil() {
    }

    /**
     * Converts to {@link BigInteger}.
     *
     * @param o
     *            The object to convert
     * @return The converted {@link BigInteger}
     */

import org.jspecify.annotations.Nullable;

/**
 * A {@link Collection} whose contents will never change, and which offers a few additional
 * guarantees detailed below.
 *
 * <p><b>Warning:</b> avoid <i>direct</i> usage of {@link ImmutableCollection} as a type (just as
 * with {@link Collection} itself). Prefer subtypes such as {@link ImmutableSet} or {@link
 * ImmutableList}, which have well-defined {@link #equals} semantics, thus avoiding a common source

 * the License.
 */

/**
 * Concurrency utilities.
 *
 * <p>Commonly used types include {@link ClosingFuture}, {@link ListenableFuture}, and {@link
 * Service}.
 *
 * <p>Commonly used utilities include {@link Futures}, {@link MoreExecutors}, {@link
 * ThreadFactoryBuilder}, and {@link Uninterruptibles}.
 *
 * <p>This package is a part of the open-source <a href="https://github.com/google/guava">Guava</a>

 *   <li>{@link #elevateWord()} - Returns an instance of ElevateWordSettings.</li>
 * </ul>
 *
 * <p>Timeout settings can be accessed via:</p>
 * <ul>
 *   <li>{@link #getScrollTimeout()}</li>
 *   <li>{@link #getSearchTimeout()}</li>
 *   <li>{@link #getIndexTimeout()}</li>
 *   <li>{@link #getIndicesTimeout()}</li>
 *   <li>{@link #getBulkTimeout()}</li>
 *   <li>{@link #getClusterTimeout()}</li>
 * </ul>
 *

    }

    /**
     * Returns a new instance of {@link DocumentBuilderFactory}.
     *
     * @return A new instance of {@link DocumentBuilderFactory}.
     */
    public static DocumentBuilderFactory newInstance() {
        return newInstance(false);
    }

    /**
     * Returns a new instance of {@link DocumentBuilderFactory}.
     *
     * @param external

  /**
   * Compares the specified object with this instance for equality. Returns {@code true} if the
   * given object is also a {@code MapDifference} and the values returned by the {@link
   * #entriesOnlyOnLeft()}, {@link #entriesOnlyOnRight()}, {@link #entriesInCommon()} and {@link
   * #entriesDiffering()} of the two instances are equal.
   */
  @Override
  boolean equals(@Nullable Object object);

  /**

import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Most of the logic for {@link IteratorTester} and {@link ListIteratorTester}.
 *
 * @param <E> the type of element returned by the iterator
 * @param <I> the type of the iterator ({@link Iterator} or {@link ListIterator})
 * @author Kevin Bourrillion
 * @author Chris Povirk
 */
@GwtCompatible
@NullMarked

  /**
   * Returns the contained instance, which must be present. If the instance might be absent, use
   * {@link #or(Object)} or {@link #orNull} instead.
   *
   * <p><b>Comparison to {@code java.util.Optional}:</b> when the value is absent, this method
   * throws {@link IllegalStateException}, whereas the {@code java.util} counterpart throws {@link
   * java.util.NoSuchElementException NoSuchElementException}.
   *

import org.jspecify.annotations.Nullable;

/**
 * A {@link BiMap} whose contents will never change, with many other important properties detailed
 * at {@link ImmutableCollection}.
 *
 * @author Jared Levy
 * @since 2.0
 */
@GwtCompatible
public abstract class ImmutableBiMap<K, V> extends ImmutableMap<K, V> implements BiMap<K, V> {

  /**