Collection<? extends Callable<T>> tasks, long timeout, TimeUnit unit)
      throws InterruptedException;

  /**
   * Duration-based overload of {@link #invokeAll(Collection, long, TimeUnit)}.
   *
   * @since 32.1.0
   */
  @J2ktIncompatible
  default <T extends @Nullable Object> List<Future<T>> invokeAll(

    new ForwardingWrapperTester()
        .testForwarding(
            Collection.class,
            new Function<Collection, Collection>() {
              @Override
              public Collection apply(Collection delegate) {
                return wrap(delegate);
              }
            });
  }

  private static <T> Collection<T> wrap(Collection<T> delegate) {
    return new ForwardingCollection<T>() {
      @Override

  public void testToArray_noArgs() {
    Object[] array = collection.toArray();
    expectArrayContentsAnyOrder(createSamplesArray(), array);
  }

  /**
   * {@link Collection#toArray(Object[])} says: "Note that {@code toArray(new Object[0])} is
   * identical in function to {@code toArray()}."
   *
   * <p>For maximum effect, the collection under test should be created from an element array of a

    final OneSizeTestContainerGenerator<Collection<E>, E> gen;

    private ReserializedCollectionGenerator(OneSizeTestContainerGenerator<Collection<E>, E> gen) {
      this.gen = gen;
    }

    @Override
    public SampleElements<E> samples() {
      return gen.samples();
    }

    @Override
    public Collection<E> create(Object... elements) {

      // Only trust the size of `values` if it is a Set and therefore probably already deduplicated.
      if (values instanceof Set<?>) {
        Set<?> collection = (Set<?>) values;
        return max(defaultExpectedValues, collection.size());
      } else {
        return defaultExpectedValues;
      }
    }

    /**
     * {@inheritDoc}
     *

    for (Collection<V> collection : asMap().values()) {
      if (collection.contains(value)) {
        return true;
      }
    }

    return false;
  }

  @Override
  public boolean containsEntry(@Nullable Object key, @Nullable Object value) {
    Collection<V> collection = asMap().get(key);
    return collection != null && collection.contains(value);
  }

  @CanIgnoreReturnValue

import com.google.common.collect.testing.features.CollectionSize;
import java.util.Collection;
import java.util.ConcurrentModificationException;
import java.util.Iterator;
import java.util.function.Predicate;
import org.junit.Ignore;

/**
 * A generic JUnit test which tests {@link Collection#removeIf}. Can't be invoked directly; please
 * see {@link com.google.common.collect.testing.CollectionTestSuiteBuilder}.

     * .
     */
    @Test
    public void testIsNotEmptyCollectionOfQ() {
        final Collection<String> c = new ArrayList<String>();
        c.add("hoge");
        assertThat(CollectionsUtil.isNotEmpty(c), is(true));
    }

    /**
     * Test method for
     * {@link org.codelibs.core.collection.CollectionsUtil#isEmpty(java.util.Map)}
     * .
     */

        if (entry.getKey().equals(key)) {
          expectedValues.add(entry.getValue());
        }
      }

      Collection<V> collection = multimap().asMap().get(key);
      if (expectedValues.isEmpty()) {
        assertNull(collection);
      } else {
        assertEqualIgnoringOrder(expectedValues, collection);
      }
    }
  }

  @CollectionSize.Require(absent = ZERO)
  @MapFeature.Require(ALLOWS_NULL_KEYS)

    return super.keySet();
  }

  /**
   * Returns a collection of all values in the multimap. Changes to the returned collection will
   * update the underlying multimap, and vice versa.
   *
   * <p>The iterator generated by the returned collection traverses the values in the order they
   * were added to the multimap.
   */
  @Override
  public Collection<V> values() {
    return super.values();
  }