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 * </p> 028 * 029 * @param <E> the type of the elements in this set 030 * @since 3.0 031 */ 032public abstract class AbstractSetDecorator<E> extends AbstractCollectionDecorator<E> implements 033 Set<E> { 034 035 /** Serialization version */ 036 private static final long serialVersionUID = -4678668309576958546L; 037 038 /** 039 * Constructor only used in deserialization, do not use otherwise. 040 * @since 3.1 041 */ 042 protected AbstractSetDecorator() { 043 super(); 044 } 045 046 /** 047 * Constructor that wraps (not copies). 048 * 049 * @param set the set to decorate, must not be null 050 * @throws NullPointerException if set is null 051 */ 052 protected AbstractSetDecorator(final Set<E> set) { 053 super(set); 054 } 055 056 /** 057 * Gets the set being decorated. 058 * 059 * @return the decorated set 060 */ 061 @Override 062 protected Set<E> decorated() { 063 return (Set<E>) super.decorated(); 064 } 065 066 @Override 067 public boolean equals(final Object object) { 068 return object == this || decorated().equals(object); 069 } 070 071 @Override 072 public int hashCode() { 073 return decorated().hashCode(); 074 } 075 076}