001/* 002 * Copyright 2008-2017 UnboundID Corp. 003 * All Rights Reserved. 004 */ 005/* 006 * Copyright (C) 2008-2017 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 */ 021package com.unboundid.util; 022 023 024 025import 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@NotMutable() 038@ThreadSafety(level=ThreadSafetyLevel.COMPLETELY_THREADSAFE) 039public final class ObjectPair<F,S> 040 implements Serializable 041{ 042 /** 043 * The serial version UID for this serializable class. 044 */ 045 private static final long serialVersionUID = -8610279945233778440L; 046 047 048 049 // The first object in this pair. 050 private final F first; 051 052 // The second object in this pair. 053 private final S second; 054 055 056 057 /** 058 * Creates a new object pair with the provided elements. 059 * 060 * @param first The first object in this pair. 061 * @param second The second object in this pair. 062 */ 063 public ObjectPair(final F first, final S second) 064 { 065 this.first = first; 066 this.second = second; 067 } 068 069 070 071 /** 072 * Retrieves the first object in this pair. 073 * 074 * @return The first object in this pair. 075 */ 076 public F getFirst() 077 { 078 return first; 079 } 080 081 082 083 /** 084 * Retrieves the second object in this pair. 085 * 086 * @return The second object in this pair. 087 */ 088 public S getSecond() 089 { 090 return second; 091 } 092 093 094 095 /** 096 * Retrieves a hash code for this object pair. 097 * 098 * @return A hash code for this object pair. 099 */ 100 @Override() 101 public int hashCode() 102 { 103 int h = 0; 104 105 if (first != null) 106 { 107 h += first.hashCode(); 108 } 109 110 if (second != null) 111 { 112 h += second.hashCode(); 113 } 114 115 return h; 116 } 117 118 119 120 /** 121 * Indicates whether the provided object is equal to this object pair. 122 * 123 * @param o The object for which to make the determination. 124 * 125 * @return {@code true} if the provided object is equal to this object pair, 126 * or {@code false} if not. 127 */ 128 @Override() 129 public boolean equals(final Object o) 130 { 131 if (o == null) 132 { 133 return false; 134 } 135 136 if (o == this) 137 { 138 return true; 139 } 140 141 if (o instanceof ObjectPair) 142 { 143 final ObjectPair<?,?> p = (ObjectPair<?,?>) o; 144 if (first == null) 145 { 146 if (p.first != null) 147 { 148 return false; 149 } 150 } 151 else 152 { 153 if (! first.equals(p.first)) 154 { 155 return false; 156 } 157 } 158 159 if (second == null) 160 { 161 if (p.second != null) 162 { 163 return false; 164 } 165 } 166 else 167 { 168 if (! second.equals(p.second)) 169 { 170 return false; 171 } 172 } 173 174 return true; 175 } 176 177 return false; 178 } 179 180 181 182 /** 183 * Retrieves a string representation of this object pair. 184 * 185 * @return A string representation of this object pair. 186 */ 187 @Override() 188 public String toString() 189 { 190 final StringBuilder buffer = new StringBuilder(); 191 toString(buffer); 192 return buffer.toString(); 193 } 194 195 196 197 /** 198 * Appends a string representation of this object pair to the provided buffer. 199 * 200 * @param buffer The buffer to which the information should be appended. 201 */ 202 public void toString(final StringBuilder buffer) 203 { 204 buffer.append("ObjectPair(first="); 205 buffer.append(String.valueOf(first)); 206 buffer.append(", second="); 207 buffer.append(String.valueOf(second)); 208 buffer.append(')'); 209 } 210}