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.builder;
18
19 import java.lang.reflect.AccessibleObject;
20 import java.lang.reflect.Field;
21 import java.lang.reflect.Modifier;
22 import java.util.ArrayList;
23 import java.util.Collection;
24 import java.util.HashSet;
25 import java.util.List;
26 import java.util.Set;
27
28 import org.apache.commons.lang3.ArrayUtils;
29 import org.apache.commons.lang3.ClassUtils;
30 import org.apache.commons.lang3.tuple.Pair;
31
32 /**
33 * Assists in implementing {@link Object#equals(Object)} methods.
34 *
35 * <p> This class provides methods to build a good equals method for any
36 * class. It follows rules laid out in
37 * <a href="https://www.oracle.com/java/technologies/effectivejava.html">Effective Java</a>
38 * , by Joshua Bloch. In particular the rule for comparing {@code doubles},
39 * {@code floats}, and arrays can be tricky. Also, making sure that
40 * {@code equals()} and {@code hashCode()} are consistent can be
41 * difficult.</p>
42 *
43 * <p>Two Objects that compare as equals must generate the same hash code,
44 * but two Objects with the same hash code do not have to be equal.</p>
45 *
46 * <p>All relevant fields should be included in the calculation of equals.
47 * Derived fields may be ignored. In particular, any field used in
48 * generating a hash code must be used in the equals method, and vice
49 * versa.</p>
50 *
51 * <p>Typical use for the code is as follows:</p>
52 * <pre>
53 * public boolean equals(Object obj) {
54 * if (obj == null) { return false; }
55 * if (obj == this) { return true; }
56 * if (obj.getClass() != getClass()) {
57 * return false;
58 * }
59 * MyClass rhs = (MyClass) obj;
60 * return new EqualsBuilder()
61 * .appendSuper(super.equals(obj))
62 * .append(field1, rhs.field1)
63 * .append(field2, rhs.field2)
64 * .append(field3, rhs.field3)
65 * .isEquals();
66 * }
67 * </pre>
68 *
69 * <p> Alternatively, there is a method that uses reflection to determine
70 * the fields to test. Because these fields are usually private, the method,
71 * {@code reflectionEquals}, uses {@code AccessibleObject.setAccessible} to
72 * change the visibility of the fields. This will fail under a security
73 * manager, unless the appropriate permissions are set up correctly. It is
74 * also slower than testing explicitly. Non-primitive fields are compared using
75 * {@code equals()}.</p>
76 *
77 * <p> A typical invocation for this method would look like:</p>
78 * <pre>
79 * public boolean equals(Object obj) {
80 * return EqualsBuilder.reflectionEquals(this, obj);
81 * }
82 * </pre>
83 *
84 * <p>The {@link EqualsExclude} annotation can be used to exclude fields from being
85 * used by the {@code reflectionEquals} methods.</p>
86 *
87 * @since 1.0
88 */
89 public class EqualsBuilder implements Builder<Boolean> {
90
91 /**
92 * A registry of objects used by reflection methods to detect cyclical object references and avoid infinite loops.
93 *
94 * @since 3.0
95 */
96 private static final ThreadLocal<Set<Pair<IDKey, IDKey>>> REGISTRY = new ThreadLocal<>();
97
98 /*
99 * NOTE: we cannot store the actual objects in a HashSet, as that would use the very hashCode()
100 * we are in the process of calculating.
101 *
102 * So we generate a one-to-one mapping from the original object to a new object.
103 *
104 * Now HashSet uses equals() to determine if two elements with the same hash code really
105 * are equal, so we also need to ensure that the replacement objects are only equal
106 * if the original objects are identical.
107 *
108 * The original implementation (2.4 and before) used the System.identityHashCode()
109 * method - however this is not guaranteed to generate unique ids (e.g. LANG-459)
110 *
111 * We now use the IDKey helper class (adapted from org.apache.axis.utils.IDKey)
112 * to disambiguate the duplicate ids.
113 */
114
115 /**
116 * Converters value pair into a register pair.
117 *
118 * @param lhs {@code this} object
119 * @param rhs the other object
120 *
121 * @return the pair
122 */
123 static Pair<IDKey, IDKey> getRegisterPair(final Object lhs, final Object rhs) {
124 final IDKey left = new IDKey(lhs);
125 final IDKey right = new IDKey(rhs);
126 return Pair.of(left, right);
127 }
128
129 /**
130 * Returns the registry of object pairs being traversed by the reflection
131 * methods in the current thread.
132 *
133 * @return Set the registry of objects being traversed
134 * @since 3.0
135 */
136 static Set<Pair<IDKey, IDKey>> getRegistry() {
137 return REGISTRY.get();
138 }
139
140 /**
141 * Returns {@code true} if the registry contains the given object pair.
142 * Used by the reflection methods to avoid infinite loops.
143 * Objects might be swapped therefore a check is needed if the object pair
144 * is registered in given or swapped order.
145 *
146 * @param lhs {@code this} object to lookup in registry
147 * @param rhs the other object to lookup on registry
148 * @return boolean {@code true} if the registry contains the given object.
149 * @since 3.0
150 */
151 static boolean isRegistered(final Object lhs, final Object rhs) {
152 final Set<Pair<IDKey, IDKey>> registry = getRegistry();
153 final Pair<IDKey, IDKey> pair = getRegisterPair(lhs, rhs);
154 final Pair<IDKey, IDKey> swappedPair = Pair.of(pair.getRight(), pair.getLeft());
155
156 return registry != null
157 && (registry.contains(pair) || registry.contains(swappedPair));
158 }
159
160 /**
161 * This method uses reflection to determine if the two {@link Object}s
162 * are equal.
163 *
164 * <p>It uses {@code AccessibleObject.setAccessible} to gain access to private
165 * fields. This means that it will throw a security exception if run under
166 * a security manager, if the permissions are not set up correctly. It is also
167 * not as efficient as testing explicitly. Non-primitive fields are compared using
168 * {@code equals()}.</p>
169 *
170 * <p>If the TestTransients parameter is set to {@code true}, transient
171 * members will be tested, otherwise they are ignored, as they are likely
172 * derived fields, and not part of the value of the {@link Object}.</p>
173 *
174 * <p>Static fields will not be tested. Superclass fields will be included.</p>
175 *
176 * @param lhs {@code this} object
177 * @param rhs the other object
178 * @param testTransients whether to include transient fields
179 * @return {@code true} if the two Objects have tested equals.
180 *
181 * @see EqualsExclude
182 */
183 public static boolean reflectionEquals(final Object lhs, final Object rhs, final boolean testTransients) {
184 return reflectionEquals(lhs, rhs, testTransients, null);
185 }
186
187 /**
188 * This method uses reflection to determine if the two {@link Object}s
189 * are equal.
190 *
191 * <p>It uses {@code AccessibleObject.setAccessible} to gain access to private
192 * fields. This means that it will throw a security exception if run under
193 * a security manager, if the permissions are not set up correctly. It is also
194 * not as efficient as testing explicitly. Non-primitive fields are compared using
195 * {@code equals()}.</p>
196 *
197 * <p>If the testTransients parameter is set to {@code true}, transient
198 * members will be tested, otherwise they are ignored, as they are likely
199 * derived fields, and not part of the value of the {@link Object}.</p>
200 *
201 * <p>Static fields will not be included. Superclass fields will be appended
202 * up to and including the specified superclass. A null superclass is treated
203 * as java.lang.Object.</p>
204 *
205 * <p>If the testRecursive parameter is set to {@code true}, non primitive
206 * (and non primitive wrapper) field types will be compared by
207 * {@link EqualsBuilder} recursively instead of invoking their
208 * {@code equals()} method. Leading to a deep reflection equals test.
209 *
210 * @param lhs {@code this} object
211 * @param rhs the other object
212 * @param testTransients whether to include transient fields
213 * @param reflectUpToClass the superclass to reflect up to (inclusive),
214 * may be {@code null}
215 * @param testRecursive whether to call reflection equals on non-primitive
216 * fields recursively.
217 * @param excludeFields array of field names to exclude from testing
218 * @return {@code true} if the two Objects have tested equals.
219 *
220 * @see EqualsExclude
221 * @since 3.6
222 */
223 public static boolean reflectionEquals(final Object lhs, final Object rhs, final boolean testTransients, final Class<?> reflectUpToClass,
224 final boolean testRecursive, final String... excludeFields) {
225 if (lhs == rhs) {
226 return true;
227 }
228 if (lhs == null || rhs == null) {
229 return false;
230 }
231 return new EqualsBuilder()
232 .setExcludeFields(excludeFields)
233 .setReflectUpToClass(reflectUpToClass)
234 .setTestTransients(testTransients)
235 .setTestRecursive(testRecursive)
236 .reflectionAppend(lhs, rhs)
237 .isEquals();
238 }
239
240 /**
241 * This method uses reflection to determine if the two {@link Object}s
242 * are equal.
243 *
244 * <p>It uses {@code AccessibleObject.setAccessible} to gain access to private
245 * fields. This means that it will throw a security exception if run under
246 * a security manager, if the permissions are not set up correctly. It is also
247 * not as efficient as testing explicitly. Non-primitive fields are compared using
248 * {@code equals()}.</p>
249 *
250 * <p>If the testTransients parameter is set to {@code true}, transient
251 * members will be tested, otherwise they are ignored, as they are likely
252 * derived fields, and not part of the value of the {@link Object}.</p>
253 *
254 * <p>Static fields will not be included. Superclass fields will be appended
255 * up to and including the specified superclass. A null superclass is treated
256 * as java.lang.Object.</p>
257 *
258 * @param lhs {@code this} object
259 * @param rhs the other object
260 * @param testTransients whether to include transient fields
261 * @param reflectUpToClass the superclass to reflect up to (inclusive),
262 * may be {@code null}
263 * @param excludeFields array of field names to exclude from testing
264 * @return {@code true} if the two Objects have tested equals.
265 *
266 * @see EqualsExclude
267 * @since 2.0
268 */
269 public static boolean reflectionEquals(final Object lhs, final Object rhs, final boolean testTransients, final Class<?> reflectUpToClass,
270 final String... excludeFields) {
271 return reflectionEquals(lhs, rhs, testTransients, reflectUpToClass, false, excludeFields);
272 }
273
274 /**
275 * This method uses reflection to determine if the two {@link Object}s
276 * are equal.
277 *
278 * <p>It uses {@code AccessibleObject.setAccessible} to gain access to private
279 * fields. This means that it will throw a security exception if run under
280 * a security manager, if the permissions are not set up correctly. It is also
281 * not as efficient as testing explicitly. Non-primitive fields are compared using
282 * {@code equals()}.</p>
283 *
284 * <p>Transient members will be not be tested, as they are likely derived
285 * fields, and not part of the value of the Object.</p>
286 *
287 * <p>Static fields will not be tested. Superclass fields will be included.</p>
288 *
289 * @param lhs {@code this} object
290 * @param rhs the other object
291 * @param excludeFields Collection of String field names to exclude from testing
292 * @return {@code true} if the two Objects have tested equals.
293 *
294 * @see EqualsExclude
295 */
296 public static boolean reflectionEquals(final Object lhs, final Object rhs, final Collection<String> excludeFields) {
297 return reflectionEquals(lhs, rhs, ReflectionToStringBuilder.toNoNullStringArray(excludeFields));
298 }
299 /**
300 * This method uses reflection to determine if the two {@link Object}s
301 * are equal.
302 *
303 * <p>It uses {@code AccessibleObject.setAccessible} to gain access to private
304 * fields. This means that it will throw a security exception if run under
305 * a security manager, if the permissions are not set up correctly. It is also
306 * not as efficient as testing explicitly. Non-primitive fields are compared using
307 * {@code equals()}.</p>
308 *
309 * <p>Transient members will be not be tested, as they are likely derived
310 * fields, and not part of the value of the Object.</p>
311 *
312 * <p>Static fields will not be tested. Superclass fields will be included.</p>
313 *
314 * @param lhs {@code this} object
315 * @param rhs the other object
316 * @param excludeFields array of field names to exclude from testing
317 * @return {@code true} if the two Objects have tested equals.
318 *
319 * @see EqualsExclude
320 */
321 public static boolean reflectionEquals(final Object lhs, final Object rhs, final String... excludeFields) {
322 return reflectionEquals(lhs, rhs, false, null, excludeFields);
323 }
324 /**
325 * Registers the given object pair.
326 * Used by the reflection methods to avoid infinite loops.
327 *
328 * @param lhs {@code this} object to register
329 * @param rhs the other object to register
330 */
331 private static void register(final Object lhs, final Object rhs) {
332 Set<Pair<IDKey, IDKey>> registry = getRegistry();
333 if (registry == null) {
334 registry = new HashSet<>();
335 REGISTRY.set(registry);
336 }
337 final Pair<IDKey, IDKey> pair = getRegisterPair(lhs, rhs);
338 registry.add(pair);
339 }
340 /**
341 * Unregisters the given object pair.
342 *
343 * <p>
344 * Used by the reflection methods to avoid infinite loops.
345 *
346 * @param lhs {@code this} object to unregister
347 * @param rhs the other object to unregister
348 * @since 3.0
349 */
350 private static void unregister(final Object lhs, final Object rhs) {
351 final Set<Pair<IDKey, IDKey>> registry = getRegistry();
352 if (registry != null) {
353 registry.remove(getRegisterPair(lhs, rhs));
354 if (registry.isEmpty()) {
355 REGISTRY.remove();
356 }
357 }
358 }
359 /**
360 * If the fields tested are equals.
361 * The default value is {@code true}.
362 */
363 private boolean isEquals = true;
364
365 private boolean testTransients;
366
367 private boolean testRecursive;
368
369 private List<Class<?>> bypassReflectionClasses;
370
371 private Class<?> reflectUpToClass;
372
373 private String[] excludeFields;
374
375 /**
376 * Constructor for EqualsBuilder.
377 *
378 * <p>Starts off assuming that equals is {@code true}.</p>
379 * @see Object#equals(Object)
380 */
381 public EqualsBuilder() {
382 // set up default classes to bypass reflection for
383 bypassReflectionClasses = new ArrayList<>(1);
384 bypassReflectionClasses.add(String.class); //hashCode field being lazy but not transient
385 }
386
387
388 /**
389 * Test if two {@code booleans}s are equal.
390 *
391 * @param lhs the left-hand {@code boolean}
392 * @param rhs the right-hand {@code boolean}
393 * @return this
394 */
395 public EqualsBuilder append(final boolean lhs, final boolean rhs) {
396 if (!isEquals) {
397 return this;
398 }
399 isEquals = lhs == rhs;
400 return this;
401 }
402
403 /**
404 * Deep comparison of array of {@code boolean}. Length and all
405 * values are compared.
406 *
407 * <p>The method {@link #append(boolean, boolean)} is used.</p>
408 *
409 * @param lhs the left-hand {@code boolean[]}
410 * @param rhs the right-hand {@code boolean[]}
411 * @return this
412 */
413 public EqualsBuilder append(final boolean[] lhs, final boolean[] rhs) {
414 if (!isEquals) {
415 return this;
416 }
417 if (lhs == rhs) {
418 return this;
419 }
420 if (lhs == null || rhs == null) {
421 this.setEquals(false);
422 return this;
423 }
424 if (lhs.length != rhs.length) {
425 this.setEquals(false);
426 return this;
427 }
428 for (int i = 0; i < lhs.length && isEquals; ++i) {
429 append(lhs[i], rhs[i]);
430 }
431 return this;
432 }
433
434 /**
435 * Test if two {@code byte}s are equal.
436 *
437 * @param lhs the left-hand {@code byte}
438 * @param rhs the right-hand {@code byte}
439 * @return this
440 */
441 public EqualsBuilder append(final byte lhs, final byte rhs) {
442 if (!isEquals) {
443 return this;
444 }
445 isEquals = lhs == rhs;
446 return this;
447 }
448
449 /**
450 * Deep comparison of array of {@code byte}. Length and all
451 * values are compared.
452 *
453 * <p>The method {@link #append(byte, byte)} is used.</p>
454 *
455 * @param lhs the left-hand {@code byte[]}
456 * @param rhs the right-hand {@code byte[]}
457 * @return this
458 */
459 public EqualsBuilder append(final byte[] lhs, final byte[] rhs) {
460 if (!isEquals) {
461 return this;
462 }
463 if (lhs == rhs) {
464 return this;
465 }
466 if (lhs == null || rhs == null) {
467 this.setEquals(false);
468 return this;
469 }
470 if (lhs.length != rhs.length) {
471 this.setEquals(false);
472 return this;
473 }
474 for (int i = 0; i < lhs.length && isEquals; ++i) {
475 append(lhs[i], rhs[i]);
476 }
477 return this;
478 }
479
480 /**
481 * Test if two {@code char}s are equal.
482 *
483 * @param lhs the left-hand {@code char}
484 * @param rhs the right-hand {@code char}
485 * @return this
486 */
487 public EqualsBuilder append(final char lhs, final char rhs) {
488 if (!isEquals) {
489 return this;
490 }
491 isEquals = lhs == rhs;
492 return this;
493 }
494
495 /**
496 * Deep comparison of array of {@code char}. Length and all
497 * values are compared.
498 *
499 * <p>The method {@link #append(char, char)} is used.</p>
500 *
501 * @param lhs the left-hand {@code char[]}
502 * @param rhs the right-hand {@code char[]}
503 * @return this
504 */
505 public EqualsBuilder append(final char[] lhs, final char[] rhs) {
506 if (!isEquals) {
507 return this;
508 }
509 if (lhs == rhs) {
510 return this;
511 }
512 if (lhs == null || rhs == null) {
513 this.setEquals(false);
514 return this;
515 }
516 if (lhs.length != rhs.length) {
517 this.setEquals(false);
518 return this;
519 }
520 for (int i = 0; i < lhs.length && isEquals; ++i) {
521 append(lhs[i], rhs[i]);
522 }
523 return this;
524 }
525
526 /**
527 * Test if two {@code double}s are equal by testing that the
528 * pattern of bits returned by {@code doubleToLong} are equal.
529 *
530 * <p>This handles NaNs, Infinities, and {@code -0.0}.</p>
531 *
532 * <p>It is compatible with the hash code generated by
533 * {@link HashCodeBuilder}.</p>
534 *
535 * @param lhs the left-hand {@code double}
536 * @param rhs the right-hand {@code double}
537 * @return this
538 */
539 public EqualsBuilder append(final double lhs, final double rhs) {
540 if (!isEquals) {
541 return this;
542 }
543 return append(Double.doubleToLongBits(lhs), Double.doubleToLongBits(rhs));
544 }
545
546 /**
547 * Deep comparison of array of {@code double}. Length and all
548 * values are compared.
549 *
550 * <p>The method {@link #append(double, double)} is used.</p>
551 *
552 * @param lhs the left-hand {@code double[]}
553 * @param rhs the right-hand {@code double[]}
554 * @return this
555 */
556 public EqualsBuilder append(final double[] lhs, final double[] rhs) {
557 if (!isEquals) {
558 return this;
559 }
560 if (lhs == rhs) {
561 return this;
562 }
563 if (lhs == null || rhs == null) {
564 this.setEquals(false);
565 return this;
566 }
567 if (lhs.length != rhs.length) {
568 this.setEquals(false);
569 return this;
570 }
571 for (int i = 0; i < lhs.length && isEquals; ++i) {
572 append(lhs[i], rhs[i]);
573 }
574 return this;
575 }
576
577 /**
578 * Test if two {@code float}s are equal by testing that the
579 * pattern of bits returned by doubleToLong are equal.
580 *
581 * <p>This handles NaNs, Infinities, and {@code -0.0}.</p>
582 *
583 * <p>It is compatible with the hash code generated by
584 * {@link HashCodeBuilder}.</p>
585 *
586 * @param lhs the left-hand {@code float}
587 * @param rhs the right-hand {@code float}
588 * @return this
589 */
590 public EqualsBuilder append(final float lhs, final float rhs) {
591 if (!isEquals) {
592 return this;
593 }
594 return append(Float.floatToIntBits(lhs), Float.floatToIntBits(rhs));
595 }
596
597 /**
598 * Deep comparison of array of {@code float}. Length and all
599 * values are compared.
600 *
601 * <p>The method {@link #append(float, float)} is used.</p>
602 *
603 * @param lhs the left-hand {@code float[]}
604 * @param rhs the right-hand {@code float[]}
605 * @return this
606 */
607 public EqualsBuilder append(final float[] lhs, final float[] rhs) {
608 if (!isEquals) {
609 return this;
610 }
611 if (lhs == rhs) {
612 return this;
613 }
614 if (lhs == null || rhs == null) {
615 this.setEquals(false);
616 return this;
617 }
618 if (lhs.length != rhs.length) {
619 this.setEquals(false);
620 return this;
621 }
622 for (int i = 0; i < lhs.length && isEquals; ++i) {
623 append(lhs[i], rhs[i]);
624 }
625 return this;
626 }
627
628 /**
629 * Test if two {@code int}s are equal.
630 *
631 * @param lhs the left-hand {@code int}
632 * @param rhs the right-hand {@code int}
633 * @return this
634 */
635 public EqualsBuilder append(final int lhs, final int rhs) {
636 if (!isEquals) {
637 return this;
638 }
639 isEquals = lhs == rhs;
640 return this;
641 }
642
643 /**
644 * Deep comparison of array of {@code int}. Length and all
645 * values are compared.
646 *
647 * <p>The method {@link #append(int, int)} is used.</p>
648 *
649 * @param lhs the left-hand {@code int[]}
650 * @param rhs the right-hand {@code int[]}
651 * @return this
652 */
653 public EqualsBuilder append(final int[] lhs, final int[] rhs) {
654 if (!isEquals) {
655 return this;
656 }
657 if (lhs == rhs) {
658 return this;
659 }
660 if (lhs == null || rhs == null) {
661 this.setEquals(false);
662 return this;
663 }
664 if (lhs.length != rhs.length) {
665 this.setEquals(false);
666 return this;
667 }
668 for (int i = 0; i < lhs.length && isEquals; ++i) {
669 append(lhs[i], rhs[i]);
670 }
671 return this;
672 }
673
674 /**
675 * Test if two {@code long} s are equal.
676 *
677 * @param lhs
678 * the left-hand {@code long}
679 * @param rhs
680 * the right-hand {@code long}
681 * @return this
682 */
683 public EqualsBuilder append(final long lhs, final long rhs) {
684 if (!isEquals) {
685 return this;
686 }
687 isEquals = lhs == rhs;
688 return this;
689 }
690
691 /**
692 * Deep comparison of array of {@code long}. Length and all
693 * values are compared.
694 *
695 * <p>The method {@link #append(long, long)} is used.</p>
696 *
697 * @param lhs the left-hand {@code long[]}
698 * @param rhs the right-hand {@code long[]}
699 * @return this
700 */
701 public EqualsBuilder append(final long[] lhs, final long[] rhs) {
702 if (!isEquals) {
703 return this;
704 }
705 if (lhs == rhs) {
706 return this;
707 }
708 if (lhs == null || rhs == null) {
709 this.setEquals(false);
710 return this;
711 }
712 if (lhs.length != rhs.length) {
713 this.setEquals(false);
714 return this;
715 }
716 for (int i = 0; i < lhs.length && isEquals; ++i) {
717 append(lhs[i], rhs[i]);
718 }
719 return this;
720 }
721
722 /**
723 * Test if two {@link Object}s are equal using either
724 * #{@link #reflectionAppend(Object, Object)}, if object are non
725 * primitives (or wrapper of primitives) or if field {@code testRecursive}
726 * is set to {@code false}. Otherwise, using their
727 * {@code equals} method.
728 *
729 * @param lhs the left-hand object
730 * @param rhs the right-hand object
731 * @return this
732 */
733 public EqualsBuilder append(final Object lhs, final Object rhs) {
734 if (!isEquals) {
735 return this;
736 }
737 if (lhs == rhs) {
738 return this;
739 }
740 if (lhs == null || rhs == null) {
741 this.setEquals(false);
742 return this;
743 }
744 final Class<?> lhsClass = lhs.getClass();
745 if (lhsClass.isArray()) {
746 // factor out array case in order to keep method small enough
747 // to be inlined
748 appendArray(lhs, rhs);
749 } else // The simple case, not an array, just test the element
750 if (testRecursive && !ClassUtils.isPrimitiveOrWrapper(lhsClass)) {
751 reflectionAppend(lhs, rhs);
752 } else {
753 isEquals = lhs.equals(rhs);
754 }
755 return this;
756 }
757
758 /**
759 * Performs a deep comparison of two {@link Object} arrays.
760 *
761 * <p>This also will be called for the top level of
762 * multi-dimensional, ragged, and multi-typed arrays.</p>
763 *
764 * <p>Note that this method does not compare the type of the arrays; it only
765 * compares the contents.</p>
766 *
767 * @param lhs the left-hand {@code Object[]}
768 * @param rhs the right-hand {@code Object[]}
769 * @return this
770 */
771 public EqualsBuilder append(final Object[] lhs, final Object[] rhs) {
772 if (!isEquals) {
773 return this;
774 }
775 if (lhs == rhs) {
776 return this;
777 }
778 if (lhs == null || rhs == null) {
779 this.setEquals(false);
780 return this;
781 }
782 if (lhs.length != rhs.length) {
783 this.setEquals(false);
784 return this;
785 }
786 for (int i = 0; i < lhs.length && isEquals; ++i) {
787 append(lhs[i], rhs[i]);
788 }
789 return this;
790 }
791
792 /**
793 * Test if two {@code short}s are equal.
794 *
795 * @param lhs the left-hand {@code short}
796 * @param rhs the right-hand {@code short}
797 * @return this
798 */
799 public EqualsBuilder append(final short lhs, final short rhs) {
800 if (!isEquals) {
801 return this;
802 }
803 isEquals = lhs == rhs;
804 return this;
805 }
806
807 /**
808 * Deep comparison of array of {@code short}. Length and all
809 * values are compared.
810 *
811 * <p>The method {@link #append(short, short)} is used.</p>
812 *
813 * @param lhs the left-hand {@code short[]}
814 * @param rhs the right-hand {@code short[]}
815 * @return this
816 */
817 public EqualsBuilder append(final short[] lhs, final short[] rhs) {
818 if (!isEquals) {
819 return this;
820 }
821 if (lhs == rhs) {
822 return this;
823 }
824 if (lhs == null || rhs == null) {
825 this.setEquals(false);
826 return this;
827 }
828 if (lhs.length != rhs.length) {
829 this.setEquals(false);
830 return this;
831 }
832 for (int i = 0; i < lhs.length && isEquals; ++i) {
833 append(lhs[i], rhs[i]);
834 }
835 return this;
836 }
837
838 /**
839 * Test if an {@link Object} is equal to an array.
840 *
841 * @param lhs the left-hand object, an array
842 * @param rhs the right-hand object
843 */
844 private void appendArray(final Object lhs, final Object rhs) {
845 // First we compare different dimensions, for example: a boolean[][] to a boolean[]
846 // then we 'Switch' on type of array, to dispatch to the correct handler
847 // This handles multidimensional arrays of the same depth
848 if (lhs.getClass() != rhs.getClass()) {
849 this.setEquals(false);
850 } else if (lhs instanceof long[]) {
851 append((long[]) lhs, (long[]) rhs);
852 } else if (lhs instanceof int[]) {
853 append((int[]) lhs, (int[]) rhs);
854 } else if (lhs instanceof short[]) {
855 append((short[]) lhs, (short[]) rhs);
856 } else if (lhs instanceof char[]) {
857 append((char[]) lhs, (char[]) rhs);
858 } else if (lhs instanceof byte[]) {
859 append((byte[]) lhs, (byte[]) rhs);
860 } else if (lhs instanceof double[]) {
861 append((double[]) lhs, (double[]) rhs);
862 } else if (lhs instanceof float[]) {
863 append((float[]) lhs, (float[]) rhs);
864 } else if (lhs instanceof boolean[]) {
865 append((boolean[]) lhs, (boolean[]) rhs);
866 } else {
867 // Not an array of primitives
868 append((Object[]) lhs, (Object[]) rhs);
869 }
870 }
871
872 /**
873 * Adds the result of {@code super.equals()} to this builder.
874 *
875 * @param superEquals the result of calling {@code super.equals()}
876 * @return this
877 * @since 2.0
878 */
879 public EqualsBuilder appendSuper(final boolean superEquals) {
880 if (!isEquals) {
881 return this;
882 }
883 isEquals = superEquals;
884 return this;
885 }
886
887 /**
888 * Returns {@code true} if the fields that have been checked
889 * are all equal.
890 *
891 * @return {@code true} if all of the fields that have been checked
892 * are equal, {@code false} otherwise.
893 *
894 * @since 3.0
895 */
896 @Override
897 public Boolean build() {
898 return Boolean.valueOf(isEquals());
899 }
900
901 /**
902 * Returns {@code true} if the fields that have been checked
903 * are all equal.
904 *
905 * @return boolean
906 */
907 public boolean isEquals() {
908 return this.isEquals;
909 }
910
911 /**
912 * Tests if two {@code objects} by using reflection.
913 *
914 * <p>It uses {@code AccessibleObject.setAccessible} to gain access to private
915 * fields. This means that it will throw a security exception if run under
916 * a security manager, if the permissions are not set up correctly. It is also
917 * not as efficient as testing explicitly. Non-primitive fields are compared using
918 * {@code equals()}.</p>
919 *
920 * <p>If the testTransients field is set to {@code true}, transient
921 * members will be tested, otherwise they are ignored, as they are likely
922 * derived fields, and not part of the value of the {@link Object}.</p>
923 *
924 * <p>Static fields will not be included. Superclass fields will be appended
925 * up to and including the specified superclass in field {@code reflectUpToClass}.
926 * A null superclass is treated as java.lang.Object.</p>
927 *
928 * <p>Field names listed in field {@code excludeFields} will be ignored.</p>
929 *
930 * <p>If either class of the compared objects is contained in
931 * {@code bypassReflectionClasses}, both objects are compared by calling
932 * the equals method of the left-hand object with the right-hand object as an argument.</p>
933 *
934 * @param lhs the left-hand object
935 * @param rhs the right-hand object
936 * @return this
937 */
938 public EqualsBuilder reflectionAppend(final Object lhs, final Object rhs) {
939 if (!isEquals) {
940 return this;
941 }
942 if (lhs == rhs) {
943 return this;
944 }
945 if (lhs == null || rhs == null) {
946 isEquals = false;
947 return this;
948 }
949
950 // Find the leaf class since there may be transients in the leaf
951 // class or in classes between the leaf and root.
952 // If we are not testing transients or a subclass has no ivars,
953 // then a subclass can test equals to a superclass.
954 final Class<?> lhsClass = lhs.getClass();
955 final Class<?> rhsClass = rhs.getClass();
956 Class<?> testClass;
957 if (lhsClass.isInstance(rhs)) {
958 testClass = lhsClass;
959 if (!rhsClass.isInstance(lhs)) {
960 // rhsClass is a subclass of lhsClass
961 testClass = rhsClass;
962 }
963 } else if (rhsClass.isInstance(lhs)) {
964 testClass = rhsClass;
965 if (!lhsClass.isInstance(rhs)) {
966 // lhsClass is a subclass of rhsClass
967 testClass = lhsClass;
968 }
969 } else {
970 // The two classes are not related.
971 isEquals = false;
972 return this;
973 }
974
975 try {
976 if (testClass.isArray()) {
977 append(lhs, rhs);
978 } else //If either class is being excluded, call normal object equals method on lhsClass.
979 if (bypassReflectionClasses != null
980 && (bypassReflectionClasses.contains(lhsClass) || bypassReflectionClasses.contains(rhsClass))) {
981 isEquals = lhs.equals(rhs);
982 } else {
983 reflectionAppend(lhs, rhs, testClass);
984 while (testClass.getSuperclass() != null && testClass != reflectUpToClass) {
985 testClass = testClass.getSuperclass();
986 reflectionAppend(lhs, rhs, testClass);
987 }
988 }
989 } catch (final IllegalArgumentException e) {
990 // In this case, we tried to test a subclass vs. a superclass and
991 // the subclass has ivars or the ivars are transient and
992 // we are testing transients.
993 // If a subclass has ivars that we are trying to test them, we get an
994 // exception and we know that the objects are not equal.
995 isEquals = false;
996 }
997 return this;
998 }
999
1000 /**
1001 * Appends the fields and values defined by the given object of the
1002 * given Class.
1003 *
1004 * @param lhs the left-hand object
1005 * @param rhs the right-hand object
1006 * @param clazz the class to append details of
1007 */
1008 private void reflectionAppend(
1009 final Object lhs,
1010 final Object rhs,
1011 final Class<?> clazz) {
1012
1013 if (isRegistered(lhs, rhs)) {
1014 return;
1015 }
1016
1017 try {
1018 register(lhs, rhs);
1019 final Field[] fields = clazz.getDeclaredFields();
1020 AccessibleObject.setAccessible(fields, true);
1021 for (int i = 0; i < fields.length && isEquals; i++) {
1022 final Field field = fields[i];
1023 if (!ArrayUtils.contains(excludeFields, field.getName())
1024 && !field.getName().contains("$")
1025 && (testTransients || !Modifier.isTransient(field.getModifiers()))
1026 && !Modifier.isStatic(field.getModifiers())
1027 && !field.isAnnotationPresent(EqualsExclude.class)) {
1028 append(Reflection.getUnchecked(field, lhs), Reflection.getUnchecked(field, rhs));
1029 }
1030 }
1031 } finally {
1032 unregister(lhs, rhs);
1033 }
1034 }
1035
1036 /**
1037 * Reset the EqualsBuilder so you can use the same object again
1038 * @since 2.5
1039 */
1040 public void reset() {
1041 this.isEquals = true;
1042 }
1043
1044 /**
1045 * Sets {@link Class}es whose instances should be compared by calling their {@code equals}
1046 * although being in recursive mode. So the fields of theses classes will not be compared recursively by reflection.
1047 *
1048 * <p>Here you should name classes having non-transient fields which are cache fields being set lazily.<br>
1049 * Prominent example being {@link String} class with its hash code cache field. Due to the importance
1050 * of the {@link String} class, it is included in the default bypasses classes. Usually, if you use
1051 * your own set of classes here, remember to include {@link String} class, too.</p>
1052 * @param bypassReflectionClasses classes to bypass reflection test
1053 * @return this
1054 * @see #setTestRecursive(boolean)
1055 * @since 3.8
1056 */
1057 public EqualsBuilder setBypassReflectionClasses(final List<Class<?>> bypassReflectionClasses) {
1058 this.bypassReflectionClasses = bypassReflectionClasses;
1059 return this;
1060 }
1061
1062 /**
1063 * Sets the {@code isEquals} value.
1064 *
1065 * @param isEquals The value to set.
1066 * @since 2.1
1067 */
1068 protected void setEquals(final boolean isEquals) {
1069 this.isEquals = isEquals;
1070 }
1071
1072 /**
1073 * Sets field names to be excluded by reflection tests.
1074 * @param excludeFields the fields to exclude
1075 * @return this
1076 * @since 3.6
1077 */
1078 public EqualsBuilder setExcludeFields(final String... excludeFields) {
1079 this.excludeFields = excludeFields;
1080 return this;
1081 }
1082
1083 /**
1084 * Sets the superclass to reflect up to at reflective tests.
1085 * @param reflectUpToClass the super class to reflect up to
1086 * @return this
1087 * @since 3.6
1088 */
1089 public EqualsBuilder setReflectUpToClass(final Class<?> reflectUpToClass) {
1090 this.reflectUpToClass = reflectUpToClass;
1091 return this;
1092 }
1093
1094 /**
1095 * Sets whether to test fields recursively, instead of using their equals method, when reflectively comparing objects.
1096 * String objects, which cache a hash value, are automatically excluded from recursive testing.
1097 * You may specify other exceptions by calling {@link #setBypassReflectionClasses(List)}.
1098 * @param testRecursive whether to do a recursive test
1099 * @return this
1100 * @see #setBypassReflectionClasses(List)
1101 * @since 3.6
1102 */
1103 public EqualsBuilder setTestRecursive(final boolean testRecursive) {
1104 this.testRecursive = testRecursive;
1105 return this;
1106 }
1107
1108 /**
1109 * Sets whether to include transient fields when reflectively comparing objects.
1110 * @param testTransients whether to test transient fields
1111 * @return this
1112 * @since 3.6
1113 */
1114 public EqualsBuilder setTestTransients(final boolean testTransients) {
1115 this.testTransients = testTransients;
1116 return this;
1117 }
1118 }