1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.lang.mutable;
18
19 /**
20 * A mutable <code>int</code> wrapper.
21 *
22 * @see Integer
23 * @since 2.1
24 * @version $Id: MutableInt.java 437554 2006-08-28 06:21:41Z bayard $
25 */
26 public class MutableInt extends Number implements Comparable, Mutable {
27
28 /**
29 * Required for serialization support.
30 *
31 * @see java.io.Serializable
32 */
33 private static final long serialVersionUID = 512176391864L;
34
35 /** The mutable value. */
36 private int value;
37
38 /**
39 * Constructs a new MutableInt with the default value of zero.
40 */
41 public MutableInt() {
42 super();
43 }
44
45 /**
46 * Constructs a new MutableInt with the specified value.
47 *
48 * @param value
49 * a value.
50 */
51 public MutableInt(int value) {
52 super();
53 this.value = value;
54 }
55
56 /**
57 * Constructs a new MutableInt with the specified value.
58 *
59 * @param value
60 * a value.
61 * @throws NullPointerException
62 * if the object is null
63 */
64 public MutableInt(Number value) {
65 super();
66 this.value = value.intValue();
67 }
68
69 //-----------------------------------------------------------------------
70 /**
71 * Gets the value as a Integer instance.
72 *
73 * @return the value as a Integer
74 */
75 public Object getValue() {
76 return new Integer(this.value);
77 }
78
79 /**
80 * Sets the value.
81 *
82 * @param value
83 * the value to set
84 */
85 public void setValue(int value) {
86 this.value = value;
87 }
88
89 /**
90 * Sets the value from any Number instance.
91 *
92 * @param value
93 * the value to set
94 * @throws NullPointerException
95 * if the object is null
96 * @throws ClassCastException
97 * if the type is not a {@link Number}
98 */
99 public void setValue(Object value) {
100 setValue(((Number) value).intValue());
101 }
102
103 //-----------------------------------------------------------------------
104 /**
105 * Increments the value.
106 *
107 * @since Commons Lang 2.2
108 */
109 public void increment() {
110 value++;
111 }
112
113 /**
114 * Decrements the value.
115 *
116 * @since Commons Lang 2.2
117 */
118 public void decrement() {
119 value--;
120 }
121
122 //-----------------------------------------------------------------------
123 /**
124 * Adds a value.
125 *
126 * @param operand
127 * the value to add
128 *
129 * @since Commons Lang 2.2
130 */
131 public void add(int operand) {
132 this.value += operand;
133 }
134
135 /**
136 * Adds a value.
137 *
138 * @param operand
139 * the value to add
140 * @throws NullPointerException
141 * if the object is null
142 *
143 * @since Commons Lang 2.2
144 */
145 public void add(Number operand) {
146 this.value += operand.intValue();
147 }
148
149 /**
150 * Subtracts a value.
151 *
152 * @param operand
153 * the value to add
154 *
155 * @since Commons Lang 2.2
156 */
157 public void subtract(int operand) {
158 this.value -= operand;
159 }
160
161 /**
162 * Subtracts a value.
163 *
164 * @param operand
165 * the value to add
166 * @throws NullPointerException
167 * if the object is null
168 *
169 * @since Commons Lang 2.2
170 */
171 public void subtract(Number operand) {
172 this.value -= operand.intValue();
173 }
174
175 //-----------------------------------------------------------------------
176 // shortValue and bytValue rely on Number implementation
177 /**
178 * Returns the value of this MutableInt as a int.
179 *
180 * @return the numeric value represented by this object after conversion to type int.
181 */
182 public int intValue() {
183 return value;
184 }
185
186 /**
187 * Returns the value of this MutableInt as a long.
188 *
189 * @return the numeric value represented by this object after conversion to type long.
190 */
191 public long longValue() {
192 return value;
193 }
194
195 /**
196 * Returns the value of this MutableInt as a float.
197 *
198 * @return the numeric value represented by this object after conversion to type float.
199 */
200 public float floatValue() {
201 return value;
202 }
203
204 /**
205 * Returns the value of this MutableInt as a double.
206 *
207 * @return the numeric value represented by this object after conversion to type double.
208 */
209 public double doubleValue() {
210 return value;
211 }
212
213 //-----------------------------------------------------------------------
214 /**
215 * Gets this mutable as an instance of Integer.
216 *
217 * @return a Integer instance containing the value from this mutable
218 */
219 public Integer toInteger() {
220 return new Integer(intValue());
221 }
222
223 //-----------------------------------------------------------------------
224 /**
225 * Compares this object to the specified object. The result is <code>true</code> if and only if the argument is
226 * not <code>null</code> and is an <code>MutableInt</code> object that contains the same <code>int</code> value
227 * as this object.
228 *
229 * @param obj
230 * the object to compare with.
231 * @return <code>true</code> if the objects are the same; <code>false</code> otherwise.
232 */
233 public boolean equals(Object obj) {
234 if (obj instanceof MutableInt) {
235 return value == ((MutableInt) obj).intValue();
236 }
237 return false;
238 }
239
240 /**
241 * Returns a suitable hashcode for this mutable.
242 *
243 * @return a suitable hashcode
244 */
245 public int hashCode() {
246 return value;
247 }
248
249 /**
250 * Compares this mutable to another in ascending order.
251 *
252 * @param obj
253 * the mutable to compare to
254 * @return negative if this is less, zero if equal, positive if greater
255 * @throws ClassCastException if the argument is not a MutableInt
256 */
257 public int compareTo(Object obj) {
258 MutableInt other = (MutableInt) obj;
259 int anotherVal = other.value;
260 return value < anotherVal ? -1 : (value == anotherVal ? 0 : 1);
261 }
262
263 /**
264 * Returns the String value of this mutable.
265 *
266 * @return the mutable value as a string
267 */
268 public String toString() {
269 return String.valueOf(value);
270 }
271
272 }