001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.commons.collections4.set; 018 019import java.util.Set; 020 021import org.apache.commons.collections4.collection.AbstractCollectionDecorator; 022 023/** 024 * Decorates another <code>Set</code> to provide additional behaviour. 025 * <p> 026 * Methods are forwarded directly to the decorated set. 027 * 028 * @param <E> the type of the elements in this set 029 * @since 3.0 030 */ 031public abstract class AbstractSetDecorator<E> extends AbstractCollectionDecorator<E> implements 032 Set<E> { 033 034 /** Serialization version */ 035 private static final long serialVersionUID = -4678668309576958546L; 036 037 /** 038 * Constructor only used in deserialization, do not use otherwise. 039 * @since 3.1 040 */ 041 protected AbstractSetDecorator() { 042 super(); 043 } 044 045 /** 046 * Constructor that wraps (not copies). 047 * 048 * @param set the set to decorate, must not be null 049 * @throws NullPointerException if set is null 050 */ 051 protected AbstractSetDecorator(final Set<E> set) { 052 super(set); 053 } 054 055 /** 056 * Gets the set being decorated. 057 * 058 * @return the decorated set 059 */ 060 @Override 061 protected Set<E> decorated() { 062 return (Set<E>) super.decorated(); 063 } 064 065 @Override 066 public boolean equals(final Object object) { 067 return object == this || decorated().equals(object); 068 } 069 070 @Override 071 public int hashCode() { 072 return decorated().hashCode(); 073 } 074 075}