* effort required to implement this interface.
 *
 * <p>To implement a cache, the programmer needs only to extend this class and provide an
 * implementation for the {@link #put} and {@link #getIfPresent} methods. {@link #getAllPresent} is
 * implemented in terms of {@link #getIfPresent}; {@link #putAll} is implemented in terms of {@link
 * #put}, {@link #invalidateAll(Iterable)} is implemented in terms of {@link #invalidate}. The

   * differ: <? extends Object> means "non-null types," while <?> means "all types."
   */
  public ImmutableMap<K, V> getAllPresent(Iterable<? extends Object> keys) {
    return delegate().getAllPresent(keys);
  }

  /**
   * @since 11.0
   */
  @Override
  public void put(K key, V value) {
    delegate().put(key, value);
  }

  /**
   * @since 12.0

 * effort required to implement this interface.
 *
 * <p>To implement a cache, the programmer needs only to extend this class and provide an
 * implementation for the {@link #put} and {@link #getIfPresent} methods. {@link #getAllPresent} is
 * implemented in terms of {@link #getIfPresent}; {@link #putAll} is implemented in terms of {@link
 * #put}, {@link #invalidateAll(Iterable)} is implemented in terms of {@link #invalidate}. The

        new AbstractCache<Object, Object>() {
          @Override
          public @Nullable Object getIfPresent(Object key) {
            return null;
          }
        };

    assertThat(cache.getAllPresent(ImmutableList.of(new Object()))).isEmpty();
  }

  public void testGetAllPresent_cached() {
    Object cachedKey = new Object();
    Object cachedValue = new Object();
    Cache<Object, Object> cache =

  /*
   * <? extends Object> is mostly the same as <?> to plain Java. But to nullness checkers, they
   * differ: <? extends Object> means "non-null types," while <?> means "all types."
   */
  ImmutableMap<K, V> getAllPresent(Iterable<? extends Object> keys);

  /**
   * Associates {@code value} with {@code key} in this cache. If the cache previously contained a
   * value associated with {@code key}, the old value is replaced by {@code value}.

              return valueLoader.call();
            }
          });
    }

    @Override
    public ImmutableMap<K, V> getAllPresent(Iterable<?> keys) {
      return localCache.getAllPresent(keys);
    }

    @Override
    public void put(K key, V value) {
      localCache.put(key, value);
    }

    @Override