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 */ 017 package org.apache.commons.collections.functors; 018 019 import java.io.Serializable; 020 021 import org.apache.commons.collections.Predicate; 022 023 /** 024 * Predicate implementation that returns true if the input is the same object 025 * as the one stored in this predicate by equals. 026 * 027 * @since Commons Collections 3.0 028 * @version $Revision: 646777 $ $Date: 2008-04-10 13:33:15 +0100 (Thu, 10 Apr 2008) $ 029 * 030 * @author Stephen Colebourne 031 */ 032 public final class EqualPredicate implements Predicate, Serializable { 033 034 /** Serial version UID */ 035 private static final long serialVersionUID = 5633766978029907089L; 036 037 /** The value to compare to */ 038 private final Object iValue; 039 040 /** 041 * Factory to create the identity predicate. 042 * 043 * @param object the object to compare to 044 * @return the predicate 045 * @throws IllegalArgumentException if the predicate is null 046 */ 047 public static Predicate getInstance(Object object) { 048 if (object == null) { 049 return NullPredicate.INSTANCE; 050 } 051 return new EqualPredicate(object); 052 } 053 054 /** 055 * Constructor that performs no validation. 056 * Use <code>getInstance</code> if you want that. 057 * 058 * @param object the object to compare to 059 */ 060 public EqualPredicate(Object object) { 061 super(); 062 iValue = object; 063 } 064 065 /** 066 * Evaluates the predicate returning true if the input equals the stored value. 067 * 068 * @param object the input object 069 * @return true if input object equals stored value 070 */ 071 public boolean evaluate(Object object) { 072 return (iValue.equals(object)); 073 } 074 075 /** 076 * Gets the value. 077 * 078 * @return the value 079 * @since Commons Collections 3.1 080 */ 081 public Object getValue() { 082 return iValue; 083 } 084 085 }