import java.util.Map.Entry;
import java.util.Set;
import org.jspecify.annotations.Nullable;

/**
 * Implementation of {@link Multimaps#filterKeys(SetMultimap, Predicate)}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
final class FilteredKeySetMultimap<K extends @Nullable Object, V extends @Nullable Object>
    extends FilteredKeyMultimap<K, V> implements FilteredSetMultimap<K, V> {

  protected abstract ListeningExecutorService delegate();

  @Override
  public <T extends @Nullable Object> ListenableFuture<T> submit(Callable<T> task) {
    return delegate().submit(task);
  }

  @Override
  public ListenableFuture<?> submit(Runnable task) {
    return delegate().submit(task);
  }

  @Override
  public <T extends @Nullable Object> ListenableFuture<T> submit(
      Runnable task, @ParametricNullness T result) {

 * @since 2.0
 */
@GwtCompatible
public abstract class ForwardingMultiset<E extends @Nullable Object> extends ForwardingCollection<E>
    implements Multiset<E> {

  /** Constructor for use by subclasses. */
  protected ForwardingMultiset() {}

  @Override
  protected abstract Multiset<E> delegate();

  @Override
  public int count(@Nullable Object element) {
    return delegate().count(element);
  }

      new IteratorOperation() {
        @Override
        public @Nullable Object execute(Iterator<?> iterator) {
          iterator.remove();
          return null;
        }
      };

  private static final IteratorOperation NEXT_METHOD =
      new IteratorOperation() {
        @Override
        public @Nullable Object execute(Iterator<?> iterator) {
          return iterator.next();
        }

   *       </ul>
   *   <li>other method calls are dispatched to {@link #handleInvocation}.
   * </ul>
   */
  @Override
  public final @Nullable Object invoke(
      Object proxy, Method method, @Nullable Object @Nullable [] args) throws Throwable {
    if (args == null) {
      args = NO_ARGS;
    }
    if (args.length == 0 && method.getName().equals("hashCode")) {
      return hashCode();
    }

      assertTrue(Thread.holdsLock(mutex));
      return delegate.containsRow(rowKey);
    }

    @Override
    public @Nullable V get(Object rowKey, Object columnKey) {
      assertTrue(Thread.holdsLock(mutex));
      return delegate.get(rowKey, columnKey);
    }

    @Override
    public @Nullable V put(R rowKey, C columnKey, V value) {
      assertTrue(Thread.holdsLock(mutex));

 * the License.
 */

package com.google.common.base;

import com.google.common.annotations.GwtCompatible;
import org.jspecify.annotations.Nullable;

/**
 * Legacy version of {@link java.util.function.Supplier java.util.function.Supplier}. Semantically,
 * this could be a factory, generator, builder, closure, or something else entirely. No guarantees

@GwtIncompatible // not worth using in GWT for now
final class CompactLinkedHashMap<K extends @Nullable Object, V extends @Nullable Object>
    extends CompactHashMap<K, V> {
  // TODO(lowasser): implement removeEldestEntry so this can be used as a drop-in replacement

  /** Creates an empty {@code CompactLinkedHashMap} instance. */
  public static <K extends @Nullable Object, V extends @Nullable Object>
      CompactLinkedHashMap<K, V> create() {

import java.util.List;
import java.util.Map.Entry;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * A container class for the five sample elements we need for testing.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@NullMarked
public class SampleElements<E extends @Nullable Object> implements Iterable<E> {
  // TODO: rename e3, e4 => missing1, missing2
  private final E e0;

   * a very fast escape method.
   */
  private static final class CharArrayDecorator extends CharEscaper {
    private final char[] @Nullable [] replacements;
    private final int replaceLength;

    CharArrayDecorator(char[] @Nullable [] replacements) {
      this.replacements = replacements;
      this.replaceLength = replacements.length;
    }

    /*