1 /* 2 * Copyright (C) 2007 Google Inc. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.google.common.collect; 18 19 import com.google.common.annotations.GwtCompatible; 20 21 import java.util.Set; 22 23 import javax.annotation.Nullable; 24 25 /** 26 * A set which forwards all its method calls to another set. Subclasses should 27 * override one or more methods to modify the behavior of the backing set as 28 * desired per the <a 29 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>. 30 * 31 * @see ForwardingObject 32 * @author Kevin Bourrillion 33 * @since 2010.01.04 <b>stable</b> (imported from Google Collections Library) 34 */ 35 @GwtCompatible 36 public abstract class ForwardingSet<E> extends ForwardingCollection<E> 37 implements Set<E> { 38 delegate()39 @Override protected abstract Set<E> delegate(); 40 equals(@ullable Object object)41 @Override public boolean equals(@Nullable Object object) { 42 return object == this || delegate().equals(object); 43 } 44 hashCode()45 @Override public int hashCode() { 46 return delegate().hashCode(); 47 } 48 } 49