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.lang.math;
018
019 import java.io.Serializable;
020
021 /**
022 * <p><code>IntRange</code> represents an inclusive range of <code>int</code>s.</p>
023 *
024 * @author Apache Software Foundation
025 * @since 2.0
026 * @version $Id: IntRange.java 905636 2010-02-02 14:03:32Z niallp $
027 */
028 public final class IntRange extends Range implements Serializable {
029
030 /**
031 * Required for serialization support.
032 *
033 * @see java.io.Serializable
034 */
035 private static final long serialVersionUID = 71849363892730L;
036
037 /**
038 * The minimum number in this range (inclusive).
039 */
040 private final int min;
041 /**
042 * The maximum number in this range (inclusive).
043 */
044 private final int max;
045
046 /**
047 * Cached output minObject (class is immutable).
048 */
049 private transient Integer minObject = null;
050 /**
051 * Cached output maxObject (class is immutable).
052 */
053 private transient Integer maxObject = null;
054 /**
055 * Cached output hashCode (class is immutable).
056 */
057 private transient int hashCode = 0;
058 /**
059 * Cached output toString (class is immutable).
060 */
061 private transient String toString = null;
062
063 /**
064 * <p>Constructs a new <code>IntRange</code> using the specified
065 * number as both the minimum and maximum in this range.</p>
066 *
067 * @param number the number to use for this range
068 */
069 public IntRange(int number) {
070 super();
071 this.min = number;
072 this.max = number;
073 }
074
075 /**
076 * <p>Constructs a new <code>IntRange</code> using the specified
077 * number as both the minimum and maximum in this range.</p>
078 *
079 * @param number the number to use for this range, must not be <code>null</code>
080 * @throws IllegalArgumentException if the number is <code>null</code>
081 */
082 public IntRange(Number number) {
083 super();
084 if (number == null) {
085 throw new IllegalArgumentException("The number must not be null");
086 }
087 this.min = number.intValue();
088 this.max = number.intValue();
089 if (number instanceof Integer) {
090 this.minObject = (Integer) number;
091 this.maxObject = (Integer) number;
092 }
093 }
094
095 /**
096 * <p>Constructs a new <code>IntRange</code> with the specified
097 * minimum and maximum numbers (both inclusive).</p>
098 *
099 * <p>The arguments may be passed in the order (min,max) or (max,min). The
100 * getMinimum and getMaximum methods will return the correct values.</p>
101 *
102 * @param number1 first number that defines the edge of the range, inclusive
103 * @param number2 second number that defines the edge of the range, inclusive
104 */
105 public IntRange(int number1, int number2) {
106 super();
107 if (number2 < number1) {
108 this.min = number2;
109 this.max = number1;
110 } else {
111 this.min = number1;
112 this.max = number2;
113 }
114 }
115
116 /**
117 * <p>Constructs a new <code>IntRange</code> with the specified
118 * minimum and maximum numbers (both inclusive).</p>
119 *
120 * <p>The arguments may be passed in the order (min,max) or (max,min). The
121 * getMinimum and getMaximum methods will return the correct values.</p>
122 *
123 * @param number1 first number that defines the edge of the range, inclusive
124 * @param number2 second number that defines the edge of the range, inclusive
125 * @throws IllegalArgumentException if either number is <code>null</code>
126 */
127 public IntRange(Number number1, Number number2) {
128 super();
129 if (number1 == null || number2 == null) {
130 throw new IllegalArgumentException("The numbers must not be null");
131 }
132 int number1val = number1.intValue();
133 int number2val = number2.intValue();
134 if (number2val < number1val) {
135 this.min = number2val;
136 this.max = number1val;
137 if (number2 instanceof Integer) {
138 this.minObject = (Integer) number2;
139 }
140 if (number1 instanceof Integer) {
141 this.maxObject = (Integer) number1;
142 }
143 } else {
144 this.min = number1val;
145 this.max = number2val;
146 if (number1 instanceof Integer) {
147 this.minObject = (Integer) number1;
148 }
149 if (number2 instanceof Integer) {
150 this.maxObject = (Integer) number2;
151 }
152 }
153 }
154
155 // Accessors
156 //--------------------------------------------------------------------
157
158 /**
159 * <p>Returns the minimum number in this range.</p>
160 *
161 * @return the minimum number in this range
162 */
163 public Number getMinimumNumber() {
164 if (minObject == null) {
165 minObject = new Integer(min);
166 }
167 return minObject;
168 }
169
170 /**
171 * <p>Gets the minimum number in this range as a <code>long</code>.</p>
172 *
173 * @return the minimum number in this range
174 */
175 public long getMinimumLong() {
176 return min;
177 }
178
179 /**
180 * <p>Gets the minimum number in this range as a <code>int</code>.</p>
181 *
182 * @return the minimum number in this range
183 */
184 public int getMinimumInteger() {
185 return min;
186 }
187
188 /**
189 * <p>Gets the minimum number in this range as a <code>double</code>.</p>
190 *
191 * @return the minimum number in this range
192 */
193 public double getMinimumDouble() {
194 return min;
195 }
196
197 /**
198 * <p>Gets the minimum number in this range as a <code>float</code>.</p>
199 *
200 * @return the minimum number in this range
201 */
202 public float getMinimumFloat() {
203 return min;
204 }
205
206 /**
207 * <p>Returns the maximum number in this range.</p>
208 *
209 * @return the maximum number in this range
210 */
211 public Number getMaximumNumber() {
212 if (maxObject == null) {
213 maxObject = new Integer(max);
214 }
215 return maxObject;
216 }
217
218 /**
219 * <p>Gets the maximum number in this range as a <code>long</code>.</p>
220 *
221 * @return the maximum number in this range
222 */
223 public long getMaximumLong() {
224 return max;
225 }
226
227 /**
228 * <p>Gets the maximum number in this range as a <code>int</code>.</p>
229 *
230 * @return the maximum number in this range
231 */
232 public int getMaximumInteger() {
233 return max;
234 }
235
236 /**
237 * <p>Gets the maximum number in this range as a <code>double</code>.</p>
238 *
239 * @return the maximum number in this range
240 */
241 public double getMaximumDouble() {
242 return max;
243 }
244
245 /**
246 * <p>Gets the maximum number in this range as a <code>float</code>.</p>
247 *
248 * @return the maximum number in this range
249 */
250 public float getMaximumFloat() {
251 return max;
252 }
253
254 // Tests
255 //--------------------------------------------------------------------
256
257 /**
258 * <p>Tests whether the specified <code>number</code> occurs within
259 * this range using <code>int</code> comparison.</p>
260 *
261 * <p><code>null</code> is handled and returns <code>false</code>.</p>
262 *
263 * @param number the number to test, may be <code>null</code>
264 * @return <code>true</code> if the specified number occurs within this range
265 */
266 public boolean containsNumber(Number number) {
267 if (number == null) {
268 return false;
269 }
270 return containsInteger(number.intValue());
271 }
272
273 /**
274 * <p>Tests whether the specified <code>int</code> occurs within
275 * this range using <code>int</code> comparison.</p>
276 *
277 * <p>This implementation overrides the superclass for performance as it is
278 * the most common case.</p>
279 *
280 * @param value the int to test
281 * @return <code>true</code> if the specified number occurs within this
282 * range by <code>int</code> comparison
283 */
284 public boolean containsInteger(int value) {
285 return value >= min && value <= max;
286 }
287
288 // Range tests
289 //--------------------------------------------------------------------
290
291 /**
292 * <p>Tests whether the specified range occurs entirely within this range
293 * using <code>int</code> comparison.</p>
294 *
295 * <p><code>null</code> is handled and returns <code>false</code>.</p>
296 *
297 * @param range the range to test, may be <code>null</code>
298 * @return <code>true</code> if the specified range occurs entirely within this range
299 * @throws IllegalArgumentException if the range is not of this type
300 */
301 public boolean containsRange(Range range) {
302 if (range == null) {
303 return false;
304 }
305 return containsInteger(range.getMinimumInteger()) &&
306 containsInteger(range.getMaximumInteger());
307 }
308
309 /**
310 * <p>Tests whether the specified range overlaps with this range
311 * using <code>int</code> comparison.</p>
312 *
313 * <p><code>null</code> is handled and returns <code>false</code>.</p>
314 *
315 * @param range the range to test, may be <code>null</code>
316 * @return <code>true</code> if the specified range overlaps with this range
317 */
318 public boolean overlapsRange(Range range) {
319 if (range == null) {
320 return false;
321 }
322 return range.containsInteger(min) ||
323 range.containsInteger(max) ||
324 containsInteger(range.getMinimumInteger());
325 }
326
327 // Basics
328 //--------------------------------------------------------------------
329
330 /**
331 * <p>Compares this range to another object to test if they are equal.</p>.
332 *
333 * <p>To be equal, the class, minimum and maximum must be equal.</p>
334 *
335 * @param obj the reference object with which to compare
336 * @return <code>true</code> if this object is equal
337 */
338 public boolean equals(Object obj) {
339 if (obj == this) {
340 return true;
341 }
342 if (obj instanceof IntRange == false) {
343 return false;
344 }
345 IntRange range = (IntRange) obj;
346 return min == range.min && max == range.max;
347 }
348
349 /**
350 * <p>Gets a hashCode for the range.</p>
351 *
352 * @return a hash code value for this object
353 */
354 public int hashCode() {
355 if (hashCode == 0) {
356 hashCode = 17;
357 hashCode = 37 * hashCode + getClass().hashCode();
358 hashCode = 37 * hashCode + min;
359 hashCode = 37 * hashCode + max;
360 }
361 return hashCode;
362 }
363
364 /**
365 * <p>Gets the range as a <code>String</code>.</p>
366 *
367 * <p>The format of the String is 'Range[<i>min</i>,<i>max</i>]'.</p>
368 *
369 * @return the <code>String</code> representation of this range
370 */
371 public String toString() {
372 if (toString == null) {
373 StringBuffer buf = new StringBuffer(32);
374 buf.append("Range[");
375 buf.append(min);
376 buf.append(',');
377 buf.append(max);
378 buf.append(']');
379 toString = buf.toString();
380 }
381 return toString;
382 }
383
384 /**
385 * <p>Returns an array containing all the integer values in the range.</p>
386 *
387 * @return the <code>int[]</code> representation of this range
388 * @since 2.4
389 */
390 public int[] toArray() {
391 int[] array = new int[max - min + 1];
392 for (int i = 0; i < array.length; i++) {
393 array[i] = min + i;
394 }
395
396 return array;
397 }
398 }