001 /* 002 * Copyright 2008-2015 UnboundID Corp. 003 * All Rights Reserved. 004 */ 005 /* 006 * Copyright (C) 2008-2015 UnboundID Corp. 007 * 008 * This program is free software; you can redistribute it and/or modify 009 * it under the terms of the GNU General Public License (GPLv2 only) 010 * or the terms of the GNU Lesser General Public License (LGPLv2.1 only) 011 * as published by the Free Software Foundation. 012 * 013 * This program is distributed in the hope that it will be useful, 014 * but WITHOUT ANY WARRANTY; without even the implied warranty of 015 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 016 * GNU General Public License for more details. 017 * 018 * You should have received a copy of the GNU General Public License 019 * along with this program; if not, see <http://www.gnu.org/licenses>. 020 */ 021 package com.unboundid.util; 022 023 024 025 import java.io.Serializable; 026 027 028 029 /** 030 * This class provides a typed pair of objects. It may be used whenever two 031 * objects are required but only one is allowed (e.g., returning two values from 032 * a method). 033 * 034 * @param <F> The type of the first object. 035 * @param <S> The type of the second object. 036 */ 037 public final class ObjectPair<F,S> 038 implements Serializable 039 { 040 /** 041 * The serial version UID for this serializable class. 042 */ 043 private static final long serialVersionUID = -8610279945233778440L; 044 045 046 047 // The first object in this pair. 048 private final F first; 049 050 // The second object in this pair. 051 private final S second; 052 053 054 055 /** 056 * Creates a new object pair with the provided elements. 057 * 058 * @param first The first object in this pair. 059 * @param second The second object in this pair. 060 */ 061 public ObjectPair(final F first, final S second) 062 { 063 this.first = first; 064 this.second = second; 065 } 066 067 068 069 /** 070 * Retrieves the first object in this pair. 071 * 072 * @return The first object in this pair. 073 */ 074 public F getFirst() 075 { 076 return first; 077 } 078 079 080 081 /** 082 * Retrieves the second object in this pair. 083 * 084 * @return The second object in this pair. 085 */ 086 public S getSecond() 087 { 088 return second; 089 } 090 091 092 093 /** 094 * Retrieves a hash code for this object pair. 095 * 096 * @return A hash code for this object pair. 097 */ 098 @Override() 099 public int hashCode() 100 { 101 int h = 0; 102 103 if (first != null) 104 { 105 h += first.hashCode(); 106 } 107 108 if (second != null) 109 { 110 h += second.hashCode(); 111 } 112 113 return h; 114 } 115 116 117 118 /** 119 * Indicates whether the provided object is equal to this object pair. 120 * 121 * @param o The object for which to make the determination. 122 * 123 * @return {@code true} if the provided object is equal to this object pair, 124 * or {@code false} if not. 125 */ 126 @Override() 127 public boolean equals(final Object o) 128 { 129 if (o == null) 130 { 131 return false; 132 } 133 134 if (o == this) 135 { 136 return true; 137 } 138 139 if (o instanceof ObjectPair) 140 { 141 final ObjectPair<?,?> p = (ObjectPair<?,?>) o; 142 if (first == null) 143 { 144 if (p.first != null) 145 { 146 return false; 147 } 148 } 149 else 150 { 151 if (! first.equals(p.first)) 152 { 153 return false; 154 } 155 } 156 157 if (second == null) 158 { 159 if (p.second != null) 160 { 161 return false; 162 } 163 } 164 else 165 { 166 if (! second.equals(p.second)) 167 { 168 return false; 169 } 170 } 171 172 return true; 173 } 174 175 return false; 176 } 177 178 179 180 /** 181 * Retrieves a string representation of this object pair. 182 * 183 * @return A string representation of this object pair. 184 */ 185 @Override() 186 public String toString() 187 { 188 final StringBuilder buffer = new StringBuilder(); 189 toString(buffer); 190 return buffer.toString(); 191 } 192 193 194 195 /** 196 * Appends a string representation of this object pair to the provided buffer. 197 * 198 * @param buffer The buffer to which the information should be appended. 199 */ 200 public void toString(final StringBuilder buffer) 201 { 202 buffer.append("ObjectPair(first="); 203 buffer.append(String.valueOf(first)); 204 buffer.append(", second="); 205 buffer.append(String.valueOf(second)); 206 buffer.append(')'); 207 } 208 }