Class ForwardingCache

android/guava/src/com/google/common/cache/ForwardingCache.java:36–147

A cache which forwards all its method calls to another cache. Subclasses should override one or more methods to modify the behavior of the backing cache as desired per the decorator pattern . @author Charles Fry @since 10.0

 * @since 10.0
 */
@GwtIncompatible
public abstract class ForwardingCache<K, V> extends ForwardingObject implements Cache<K, V> {

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

  @Override
  protected abstract Cache<K, V> delegate();

  /**
   * @since 11.0
   */
  @Override
  public @Nullable V getIfPresent(Object key) {
    return delegate().getIfPresent(key);
  }

  /**
   * @since 11.0
   */
  @Override
  public V get(K key, Callable<? extends V> valueLoader) throws ExecutionException {
    return delegate().get(key, valueLoader);
  }

  /**
   * @since 11.0
   */
  @Override
  /*
   * <? 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."
   */
  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
   */
  @Override
  public void putAll(Map<? extends K, ? extends V> m) {
    delegate().putAll(m);
  }

  @Override
  public void invalidate(Object key) {
    delegate().invalidate(key);
  }