| Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
| Range |
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| 2.88;2.88 | ||||
| Range$ComparableComparator |
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| 2.88;2.88 |
| 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.lang3; | |
| 18 | ||
| 19 | import java.io.Serializable; | |
| 20 | import java.util.Comparator; | |
| 21 | ||
| 22 | /** | |
| 23 | * <p>An immutable range of objects from a minimum to maximum point inclusive.</p> | |
| 24 | * | |
| 25 | * <p>The objects need to either be implementations of {@code Comparable} | |
| 26 | * or you need to supply a {@code Comparator}. </p> | |
| 27 | * | |
| 28 | * <p>#ThreadSafe# if the objects and comparator are thread-safe</p> | |
| 29 | * | |
| 30 | * @since 3.0 | |
| 31 | * @version $Id: Range.java 1436770 2013-01-22 07:09:45Z ggregory $ | |
| 32 | */ | |
| 33 | public final class Range<T> implements Serializable { | |
| 34 | ||
| 35 | /** | |
| 36 | * Serialization version. | |
| 37 | * @see java.io.Serializable | |
| 38 | */ | |
| 39 | private static final long serialVersionUID = 1L; | |
| 40 | ||
| 41 | /** | |
| 42 | * The ordering scheme used in this range. | |
| 43 | */ | |
| 44 | private final Comparator<T> comparator; | |
| 45 | /** | |
| 46 | * The minimum value in this range (inclusive). | |
| 47 | */ | |
| 48 | private final T minimum; | |
| 49 | /** | |
| 50 | * The maximum value in this range (inclusive). | |
| 51 | */ | |
| 52 | private final T maximum; | |
| 53 | /** | |
| 54 | * Cached output hashCode (class is immutable). | |
| 55 | */ | |
| 56 | private transient int hashCode; | |
| 57 | /** | |
| 58 | * Cached output toString (class is immutable). | |
| 59 | */ | |
| 60 | private transient String toString; | |
| 61 | ||
| 62 | /** | |
| 63 | * <p>Obtains a range using the specified element as both the minimum | |
| 64 | * and maximum in this range.</p> | |
| 65 | * | |
| 66 | * <p>The range uses the natural ordering of the elements to determine where | |
| 67 | * values lie in the range.</p> | |
| 68 | * | |
| 69 | * @param <T> the type of the elements in this range | |
| 70 | * @param element the value to use for this range, not null | |
| 71 | * @return the range object, not null | |
| 72 | * @throws IllegalArgumentException if the element is null | |
| 73 | * @throws ClassCastException if the element is not {@code Comparable} | |
| 74 | */ | |
| 75 | public static <T extends Comparable<T>> Range<T> is(final T element) { | |
| 76 | 2 | return between(element, element, null); |
| 77 | } | |
| 78 | ||
| 79 | /** | |
| 80 | * <p>Obtains a range using the specified element as both the minimum | |
| 81 | * and maximum in this range.</p> | |
| 82 | * | |
| 83 | * <p>The range uses the specified {@code Comparator} to determine where | |
| 84 | * values lie in the range.</p> | |
| 85 | * | |
| 86 | * @param <T> the type of the elements in this range | |
| 87 | * @param element the value to use for this range, must not be {@code null} | |
| 88 | * @param comparator the comparator to be used, null for natural ordering | |
| 89 | * @return the range object, not null | |
| 90 | * @throws IllegalArgumentException if the element is null | |
| 91 | * @throws ClassCastException if using natural ordering and the elements are not {@code Comparable} | |
| 92 | */ | |
| 93 | public static <T> Range<T> is(final T element, final Comparator<T> comparator) { | |
| 94 | 1 | return between(element, element, comparator); |
| 95 | } | |
| 96 | ||
| 97 | /** | |
| 98 | * <p>Obtains a range with the specified minimum and maximum values (both inclusive).</p> | |
| 99 | * | |
| 100 | * <p>The range uses the natural ordering of the elements to determine where | |
| 101 | * values lie in the range.</p> | |
| 102 | * | |
| 103 | * <p>The arguments may be passed in the order (min,max) or (max,min). | |
| 104 | * The getMinimum and getMaximum methods will return the correct values.</p> | |
| 105 | * | |
| 106 | * @param <T> the type of the elements in this range | |
| 107 | * @param fromInclusive the first value that defines the edge of the range, inclusive | |
| 108 | * @param toInclusive the second value that defines the edge of the range, inclusive | |
| 109 | * @return the range object, not null | |
| 110 | * @throws IllegalArgumentException if either element is null | |
| 111 | * @throws ClassCastException if the elements are not {@code Comparable} | |
| 112 | */ | |
| 113 | public static <T extends Comparable<T>> Range<T> between(final T fromInclusive, final T toInclusive) { | |
| 114 | 211 | return between(fromInclusive, toInclusive, null); |
| 115 | } | |
| 116 | ||
| 117 | /** | |
| 118 | * <p>Obtains a range with the specified minimum and maximum values (both inclusive).</p> | |
| 119 | * | |
| 120 | * <p>The range uses the specified {@code Comparator} to determine where | |
| 121 | * values lie in the range.</p> | |
| 122 | * | |
| 123 | * <p>The arguments may be passed in the order (min,max) or (max,min). | |
| 124 | * The getMinimum and getMaximum methods will return the correct values.</p> | |
| 125 | * | |
| 126 | * @param <T> the type of the elements in this range | |
| 127 | * @param fromInclusive the first value that defines the edge of the range, inclusive | |
| 128 | * @param toInclusive the second value that defines the edge of the range, inclusive | |
| 129 | * @param comparator the comparator to be used, null for natural ordering | |
| 130 | * @return the range object, not null | |
| 131 | * @throws IllegalArgumentException if either element is null | |
| 132 | * @throws ClassCastException if using natural ordering and the elements are not {@code Comparable} | |
| 133 | */ | |
| 134 | public static <T> Range<T> between(final T fromInclusive, final T toInclusive, final Comparator<T> comparator) { | |
| 135 | 216 | return new Range<T>(fromInclusive, toInclusive, comparator); |
| 136 | } | |
| 137 | ||
| 138 | /** | |
| 139 | * Creates an instance. | |
| 140 | * | |
| 141 | * @param element1 the first element, not null | |
| 142 | * @param element2 the second element, not null | |
| 143 | * @param comparator the comparator to be used, null for natural ordering | |
| 144 | */ | |
| 145 | @SuppressWarnings("unchecked") | |
| 146 | 216 | private Range(final T element1, final T element2, Comparator<T> comparator) { |
| 147 | 216 | if (element1 == null || element2 == null) { |
| 148 | 0 | throw new IllegalArgumentException("Elements in a range must not be null: element1=" + |
| 149 | element1 + ", element2=" + element2); | |
| 150 | } | |
| 151 | 216 | if (comparator == null) { |
| 152 | 213 | comparator = ComparableComparator.INSTANCE; |
| 153 | } | |
| 154 | 216 | if (comparator.compare(element1, element2) < 1) { |
| 155 | 212 | this.minimum = element1; |
| 156 | 212 | this.maximum = element2; |
| 157 | } else { | |
| 158 | 4 | this.minimum = element2; |
| 159 | 4 | this.maximum = element1; |
| 160 | } | |
| 161 | 216 | this.comparator = comparator; |
| 162 | 216 | } |
| 163 | ||
| 164 | // Accessors | |
| 165 | //-------------------------------------------------------------------- | |
| 166 | ||
| 167 | /** | |
| 168 | * <p>Gets the minimum value in this range.</p> | |
| 169 | * | |
| 170 | * @return the minimum value in this range, not null | |
| 171 | */ | |
| 172 | public T getMinimum() { | |
| 173 | 4 | return minimum; |
| 174 | } | |
| 175 | ||
| 176 | /** | |
| 177 | * <p>Gets the maximum value in this range.</p> | |
| 178 | * | |
| 179 | * @return the maximum value in this range, not null | |
| 180 | */ | |
| 181 | public T getMaximum() { | |
| 182 | 4 | return maximum; |
| 183 | } | |
| 184 | ||
| 185 | /** | |
| 186 | * <p>Gets the comparator being used to determine if objects are within the range.</p> | |
| 187 | * | |
| 188 | * <p>Natural ordering uses an internal comparator implementation, thus this | |
| 189 | * method never returns null. See {@link #isNaturalOrdering()}.</p> | |
| 190 | * | |
| 191 | * @return the comparator being used, not null | |
| 192 | */ | |
| 193 | public Comparator<T> getComparator() { | |
| 194 | 3 | return comparator; |
| 195 | } | |
| 196 | ||
| 197 | /** | |
| 198 | * <p>Whether or not the Range is using the natural ordering of the elements.</p> | |
| 199 | * | |
| 200 | * <p>Natural ordering uses an internal comparator implementation, thus this | |
| 201 | * method is the only way to check if a null comparator was specified.</p> | |
| 202 | * | |
| 203 | * @return true if using natural ordering | |
| 204 | */ | |
| 205 | public boolean isNaturalOrdering() { | |
| 206 | 2 | return comparator == ComparableComparator.INSTANCE; |
| 207 | } | |
| 208 | ||
| 209 | // Element tests | |
| 210 | //-------------------------------------------------------------------- | |
| 211 | ||
| 212 | /** | |
| 213 | * <p>Checks whether the specified element occurs within this range.</p> | |
| 214 | * | |
| 215 | * @param element the element to check for, null returns false | |
| 216 | * @return true if the specified element occurs within this range | |
| 217 | */ | |
| 218 | public boolean contains(final T element) { | |
| 219 | 71 | if (element == null) { |
| 220 | 5 | return false; |
| 221 | } | |
| 222 | 66 | return comparator.compare(element, minimum) > -1 && comparator.compare(element, maximum) < 1; |
| 223 | } | |
| 224 | ||
| 225 | /** | |
| 226 | * <p>Checks whether this range is after the specified element.</p> | |
| 227 | * | |
| 228 | * @param element the element to check for, null returns false | |
| 229 | * @return true if this range is entirely after the specified element | |
| 230 | */ | |
| 231 | public boolean isAfter(final T element) { | |
| 232 | 18 | if (element == null) { |
| 233 | 1 | return false; |
| 234 | } | |
| 235 | 17 | return comparator.compare(element, minimum) < 0; |
| 236 | } | |
| 237 | ||
| 238 | /** | |
| 239 | * <p>Checks whether this range starts with the specified element.</p> | |
| 240 | * | |
| 241 | * @param element the element to check for, null returns false | |
| 242 | * @return true if the specified element occurs within this range | |
| 243 | */ | |
| 244 | public boolean isStartedBy(final T element) { | |
| 245 | 6 | if (element == null) { |
| 246 | 1 | return false; |
| 247 | } | |
| 248 | 5 | return comparator.compare(element, minimum) == 0; |
| 249 | } | |
| 250 | ||
| 251 | /** | |
| 252 | * <p>Checks whether this range starts with the specified element.</p> | |
| 253 | * | |
| 254 | * @param element the element to check for, null returns false | |
| 255 | * @return true if the specified element occurs within this range | |
| 256 | */ | |
| 257 | public boolean isEndedBy(final T element) { | |
| 258 | 6 | if (element == null) { |
| 259 | 1 | return false; |
| 260 | } | |
| 261 | 5 | return comparator.compare(element, maximum) == 0; |
| 262 | } | |
| 263 | ||
| 264 | /** | |
| 265 | * <p>Checks whether this range is before the specified element.</p> | |
| 266 | * | |
| 267 | * @param element the element to check for, null returns false | |
| 268 | * @return true if this range is entirely before the specified element | |
| 269 | */ | |
| 270 | public boolean isBefore(final T element) { | |
| 271 | 17 | if (element == null) { |
| 272 | 1 | return false; |
| 273 | } | |
| 274 | 16 | return comparator.compare(element, maximum) > 0; |
| 275 | } | |
| 276 | ||
| 277 | /** | |
| 278 | * <p>Checks where the specified element occurs relative to this range.</p> | |
| 279 | * | |
| 280 | * <p>The API is reminiscent of the Comparable interface returning {@code -1} if | |
| 281 | * the element is before the range, {@code 0} if contained within the range and | |
| 282 | * {@code 1} if the element is after the range. </p> | |
| 283 | * | |
| 284 | * @param element the element to check for, not null | |
| 285 | * @return -1, 0 or +1 depending on the element's location relative to the range | |
| 286 | */ | |
| 287 | public int elementCompareTo(final T element) { | |
| 288 | 6 | if (element == null) { |
| 289 | // Comparable API says throw NPE on null | |
| 290 | 1 | throw new NullPointerException("Element is null"); |
| 291 | } | |
| 292 | 5 | if (isAfter(element)) { |
| 293 | 1 | return -1; |
| 294 | 4 | } else if (isBefore(element)) { |
| 295 | 1 | return 1; |
| 296 | } else { | |
| 297 | 3 | return 0; |
| 298 | } | |
| 299 | } | |
| 300 | ||
| 301 | // Range tests | |
| 302 | //-------------------------------------------------------------------- | |
| 303 | ||
| 304 | /** | |
| 305 | * <p>Checks whether this range contains all the elements of the specified range.</p> | |
| 306 | * | |
| 307 | * <p>This method may fail if the ranges have two different comparators or element types.</p> | |
| 308 | * | |
| 309 | * @param otherRange the range to check, null returns false | |
| 310 | * @return true if this range contains the specified range | |
| 311 | * @throws RuntimeException if ranges cannot be compared | |
| 312 | */ | |
| 313 | public boolean containsRange(final Range<T> otherRange) { | |
| 314 | 12 | if (otherRange == null) { |
| 315 | 1 | return false; |
| 316 | } | |
| 317 | 11 | return contains(otherRange.minimum) |
| 318 | && contains(otherRange.maximum); | |
| 319 | } | |
| 320 | ||
| 321 | /** | |
| 322 | * <p>Checks whether this range is completely after the specified range.</p> | |
| 323 | * | |
| 324 | * <p>This method may fail if the ranges have two different comparators or element types.</p> | |
| 325 | * | |
| 326 | * @param otherRange the range to check, null returns false | |
| 327 | * @return true if this range is completely after the specified range | |
| 328 | * @throws RuntimeException if ranges cannot be compared | |
| 329 | */ | |
| 330 | public boolean isAfterRange(final Range<T> otherRange) { | |
| 331 | 8 | if (otherRange == null) { |
| 332 | 1 | return false; |
| 333 | } | |
| 334 | 7 | return isAfter(otherRange.maximum); |
| 335 | } | |
| 336 | ||
| 337 | /** | |
| 338 | * <p>Checks whether this range is overlapped by the specified range.</p> | |
| 339 | * | |
| 340 | * <p>Two ranges overlap if there is at least one element in common.</p> | |
| 341 | * | |
| 342 | * <p>This method may fail if the ranges have two different comparators or element types.</p> | |
| 343 | * | |
| 344 | * @param otherRange the range to test, null returns false | |
| 345 | * @return true if the specified range overlaps with this | |
| 346 | * range; otherwise, {@code false} | |
| 347 | * @throws RuntimeException if ranges cannot be compared | |
| 348 | */ | |
| 349 | public boolean isOverlappedBy(final Range<T> otherRange) { | |
| 350 | 20 | if (otherRange == null) { |
| 351 | 2 | return false; |
| 352 | } | |
| 353 | 18 | return otherRange.contains(minimum) |
| 354 | || otherRange.contains(maximum) | |
| 355 | || contains(otherRange.minimum); | |
| 356 | } | |
| 357 | ||
| 358 | /** | |
| 359 | * <p>Checks whether this range is completely before the specified range.</p> | |
| 360 | * | |
| 361 | * <p>This method may fail if the ranges have two different comparators or element types.</p> | |
| 362 | * | |
| 363 | * @param otherRange the range to check, null returns false | |
| 364 | * @return true if this range is completely before the specified range | |
| 365 | * @throws RuntimeException if ranges cannot be compared | |
| 366 | */ | |
| 367 | public boolean isBeforeRange(final Range<T> otherRange) { | |
| 368 | 8 | if (otherRange == null) { |
| 369 | 1 | return false; |
| 370 | } | |
| 371 | 7 | return isBefore(otherRange.minimum); |
| 372 | } | |
| 373 | ||
| 374 | /** | |
| 375 | * Calculate the intersection of {@code this} and an overlapping Range. | |
| 376 | * @param other overlapping Range | |
| 377 | * @return range representing the intersection of {@code this} and {@code other} ({@code this} if equal) | |
| 378 | * @throws IllegalArgumentException if {@code other} does not overlap {@code this} | |
| 379 | * @since 3.0.1 | |
| 380 | */ | |
| 381 | public Range<T> intersectionWith(final Range<T> other) { | |
| 382 | 8 | if (!this.isOverlappedBy(other)) { |
| 383 | 2 | throw new IllegalArgumentException(String.format( |
| 384 | "Cannot calculate intersection with non-overlapping range %s", other)); | |
| 385 | } | |
| 386 | 6 | if (this.equals(other)) { |
| 387 | 5 | return this; |
| 388 | } | |
| 389 | 1 | final T min = getComparator().compare(minimum, other.minimum) < 0 ? other.minimum : minimum; |
| 390 | 1 | final T max = getComparator().compare(maximum, other.maximum) < 0 ? maximum : other.maximum; |
| 391 | 1 | return between(min, max, getComparator()); |
| 392 | } | |
| 393 | ||
| 394 | // Basics | |
| 395 | //-------------------------------------------------------------------- | |
| 396 | ||
| 397 | /** | |
| 398 | * <p>Compares this range to another object to test if they are equal.</p>. | |
| 399 | * | |
| 400 | * <p>To be equal, the minimum and maximum values must be equal, which | |
| 401 | * ignores any differences in the comparator.</p> | |
| 402 | * | |
| 403 | * @param obj the reference object with which to compare | |
| 404 | * @return true if this object is equal | |
| 405 | */ | |
| 406 | @Override | |
| 407 | public boolean equals(final Object obj) { | |
| 408 | 16 | if (obj == this) { |
| 409 | 10 | return true; |
| 410 | 6 | } else if (obj == null || obj.getClass() != getClass()) { |
| 411 | 2 | return false; |
| 412 | } else { | |
| 413 | @SuppressWarnings("unchecked") // OK because we checked the class above | |
| 414 | final | |
| 415 | 4 | Range<T> range = (Range<T>) obj; |
| 416 | 4 | return minimum.equals(range.minimum) && |
| 417 | maximum.equals(range.maximum); | |
| 418 | } | |
| 419 | } | |
| 420 | ||
| 421 | /** | |
| 422 | * <p>Gets a suitable hash code for the range.</p> | |
| 423 | * | |
| 424 | * @return a hash code value for this object | |
| 425 | */ | |
| 426 | @Override | |
| 427 | public int hashCode() { | |
| 428 | 7 | int result = hashCode; |
| 429 | 7 | if (hashCode == 0) { |
| 430 | 4 | result = 17; |
| 431 | 4 | result = 37 * result + getClass().hashCode(); |
| 432 | 4 | result = 37 * result + minimum.hashCode(); |
| 433 | 4 | result = 37 * result + maximum.hashCode(); |
| 434 | 4 | hashCode = result; |
| 435 | } | |
| 436 | 7 | return result; |
| 437 | } | |
| 438 | ||
| 439 | /** | |
| 440 | * <p>Gets the range as a {@code String}.</p> | |
| 441 | * | |
| 442 | * <p>The format of the String is '[<i>min</i>..<i>max</i>]'.</p> | |
| 443 | * | |
| 444 | * @return the {@code String} representation of this range | |
| 445 | */ | |
| 446 | @Override | |
| 447 | public String toString() { | |
| 448 | 4 | String result = toString; |
| 449 | 4 | if (result == null) { |
| 450 | 4 | final StringBuilder buf = new StringBuilder(32); |
| 451 | 4 | buf.append('['); |
| 452 | 4 | buf.append(minimum); |
| 453 | 4 | buf.append(".."); |
| 454 | 4 | buf.append(maximum); |
| 455 | 4 | buf.append(']'); |
| 456 | 4 | result = buf.toString(); |
| 457 | 4 | toString = result; |
| 458 | } | |
| 459 | 4 | return result; |
| 460 | } | |
| 461 | ||
| 462 | /** | |
| 463 | * <p>Formats the receiver using the given format.</p> | |
| 464 | * | |
| 465 | * <p>This uses {@link java.util.Formattable} to perform the formatting. Three variables may | |
| 466 | * be used to embed the minimum, maximum and comparator. | |
| 467 | * Use {@code %1$s} for the minimum element, {@code %2$s} for the maximum element | |
| 468 | * and {@code %3$s} for the comparator. | |
| 469 | * The default format used by {@code toString()} is {@code [%1$s..%2$s]}.</p> | |
| 470 | * | |
| 471 | * @param format the format string, optionally containing {@code %1$s}, {@code %2$s} and {@code %3$s}, not null | |
| 472 | * @return the formatted string, not null | |
| 473 | */ | |
| 474 | public String toString(final String format) { | |
| 475 | 1 | return String.format(format, minimum, maximum, comparator); |
| 476 | } | |
| 477 | ||
| 478 | //----------------------------------------------------------------------- | |
| 479 | 2 | @SuppressWarnings({"rawtypes", "unchecked"}) |
| 480 | 1 | private enum ComparableComparator implements Comparator { |
| 481 | 1 | INSTANCE; |
| 482 | /** | |
| 483 | * Comparable based compare implementation. | |
| 484 | * | |
| 485 | * @param obj1 left hand side of comparison | |
| 486 | * @param obj2 right hand side of comparison | |
| 487 | * @return negative, 0, positive comparison value | |
| 488 | */ | |
| 489 | @Override | |
| 490 | public int compare(final Object obj1, final Object obj2) { | |
| 491 | 364 | return ((Comparable) obj1).compareTo(obj2); |
| 492 | } | |
| 493 | } | |
| 494 | ||
| 495 | } |