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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.Collection;
23  import java.util.HashSet;
24  import java.util.Set;
25  
26  import org.apache.commons.lang3.ArrayUtils;
27  import org.apache.commons.lang3.tuple.Pair;
28  
29  /**
30   * <p>Assists in implementing {@link Object#equals(Object)} methods.</p>
31   *
32   * <p> This class provides methods to build a good equals method for any
33   * class. It follows rules laid out in
34   * <a href="http://www.oracle.com/technetwork/java/effectivejava-136174.html">Effective Java</a>
35   * , by Joshua Bloch. In particular the rule for comparing <code>doubles</code>,
36   * <code>floats</code>, and arrays can be tricky. Also, making sure that
37   * <code>equals()</code> and <code>hashCode()</code> are consistent can be
38   * difficult.</p>
39   *
40   * <p>Two Objects that compare as equals must generate the same hash code,
41   * but two Objects with the same hash code do not have to be equal.</p>
42   *
43   * <p>All relevant fields should be included in the calculation of equals.
44   * Derived fields may be ignored. In particular, any field used in
45   * generating a hash code must be used in the equals method, and vice
46   * versa.</p>
47   *
48   * <p>Typical use for the code is as follows:</p>
49   * <pre>
50   * public boolean equals(Object obj) {
51   *   if (obj == null) { return false; }
52   *   if (obj == this) { return true; }
53   *   if (obj.getClass() != getClass()) {
54   *     return false;
55   *   }
56   *   MyClass rhs = (MyClass) obj;
57   *   return new EqualsBuilder()
58   *                 .appendSuper(super.equals(obj))
59   *                 .append(field1, rhs.field1)
60   *                 .append(field2, rhs.field2)
61   *                 .append(field3, rhs.field3)
62   *                 .isEquals();
63   *  }
64   * </pre>
65   *
66   * <p> Alternatively, there is a method that uses reflection to determine
67   * the fields to test. Because these fields are usually private, the method,
68   * <code>reflectionEquals</code>, uses <code>AccessibleObject.setAccessible</code> to
69   * change the visibility of the fields. This will fail under a security
70   * manager, unless the appropriate permissions are set up correctly. It is
71   * also slower than testing explicitly.  Non-primitive fields are compared using 
72   * <code>equals()</code>.</p>
73   *
74   * <p> A typical invocation for this method would look like:</p>
75   * <pre>
76   * public boolean equals(Object obj) {
77   *   return EqualsBuilder.reflectionEquals(this, obj);
78   * }
79   * </pre>
80   * 
81   * <p>The {@link EqualsExclude} annotation can be used to exclude fields from being
82   * used by the <code>reflectionEquals</code> methods.</p>
83   *
84   * @since 1.0
85   */
86  public class EqualsBuilder implements Builder<Boolean> {
87  
88      /**
89       * <p>
90       * A registry of objects used by reflection methods to detect cyclical object references and avoid infinite loops.
91       * </p>
92       *
93       * @since 3.0
94       */
95      private static final ThreadLocal<Set<Pair<IDKey, IDKey>>> REGISTRY = new ThreadLocal<Set<Pair<IDKey, IDKey>>>();
96  
97      /*
98       * NOTE: we cannot store the actual objects in a HashSet, as that would use the very hashCode()
99       * we are in the process of calculating.
100      *
101      * So we generate a one-to-one mapping from the original object to a new object.
102      *
103      * Now HashSet uses equals() to determine if two elements with the same hashcode really
104      * are equal, so we also need to ensure that the replacement objects are only equal
105      * if the original objects are identical.
106      *
107      * The original implementation (2.4 and before) used the System.identityHashCode()
108      * method - however this is not guaranteed to generate unique ids (e.g. LANG-459)
109      *
110      * We now use the IDKey helper class (adapted from org.apache.axis.utils.IDKey)
111      * to disambiguate the duplicate ids.
112      */
113 
114     /**
115      * <p>
116      * Returns the registry of object pairs being traversed by the reflection
117      * methods in the current thread.
118      * </p>
119      *
120      * @return Set the registry of objects being traversed
121      * @since 3.0
122      */
123     static Set<Pair<IDKey, IDKey>> getRegistry() {
124         return REGISTRY.get();
125     }
126 
127     /**
128      * <p>
129      * Converters value pair into a register pair.
130      * </p>
131      *
132      * @param lhs <code>this</code> object
133      * @param rhs the other object
134      *
135      * @return the pair
136      */
137     static Pair<IDKey, IDKey> getRegisterPair(final Object lhs, final Object rhs) {
138         final IDKey left = new IDKey(lhs);
139         final IDKey right = new IDKey(rhs);
140         return Pair.of(left, right);
141     }
142 
143     /**
144      * <p>
145      * Returns <code>true</code> if the registry contains the given object pair.
146      * Used by the reflection methods to avoid infinite loops.
147      * Objects might be swapped therefore a check is needed if the object pair
148      * is registered in given or swapped order.
149      * </p>
150      *
151      * @param lhs <code>this</code> object to lookup in registry
152      * @param rhs the other object to lookup on registry
153      * @return boolean <code>true</code> if the registry contains the given object.
154      * @since 3.0
155      */
156     static boolean isRegistered(final Object lhs, final Object rhs) {
157         final Set<Pair<IDKey, IDKey>> registry = getRegistry();
158         final Pair<IDKey, IDKey> pair = getRegisterPair(lhs, rhs);
159         final Pair<IDKey, IDKey> swappedPair = Pair.of(pair.getLeft(), pair.getRight());
160 
161         return registry != null
162                 && (registry.contains(pair) || registry.contains(swappedPair));
163     }
164 
165     /**
166      * <p>
167      * Registers the given object pair.
168      * Used by the reflection methods to avoid infinite loops.
169      * </p>
170      *
171      * @param lhs <code>this</code> object to register
172      * @param rhs the other object to register
173      */
174     private static void register(final Object lhs, final Object rhs) {
175         Set<Pair<IDKey, IDKey>> registry = getRegistry();
176         if (registry == null) {
177             registry = new HashSet<Pair<IDKey, IDKey>>();
178             REGISTRY.set(registry);
179         }
180         final Pair<IDKey, IDKey> pair = getRegisterPair(lhs, rhs);
181         registry.add(pair);
182     }
183 
184     /**
185      * <p>
186      * Unregisters the given object pair.
187      * </p>
188      *
189      * <p>
190      * Used by the reflection methods to avoid infinite loops.
191      *
192      * @param lhs <code>this</code> object to unregister
193      * @param rhs the other object to unregister
194      * @since 3.0
195      */
196     private static void unregister(final Object lhs, final Object rhs) {
197         Set<Pair<IDKey, IDKey>> registry = getRegistry();
198         if (registry != null) {
199             final Pair<IDKey, IDKey> pair = getRegisterPair(lhs, rhs);
200             registry.remove(pair);
201             if (registry.isEmpty()) {
202                 REGISTRY.remove();
203             }
204         }
205     }
206 
207     /**
208      * If the fields tested are equals.
209      * The default value is <code>true</code>.
210      */
211     private boolean isEquals = true;
212 
213     /**
214      * <p>Constructor for EqualsBuilder.</p>
215      *
216      * <p>Starts off assuming that equals is <code>true</code>.</p>
217      * @see Object#equals(Object)
218      */
219     public EqualsBuilder() {
220         // do nothing for now.
221     }
222 
223     //-------------------------------------------------------------------------
224 
225     /**
226      * <p>This method uses reflection to determine if the two <code>Object</code>s
227      * are equal.</p>
228      *
229      * <p>It uses <code>AccessibleObject.setAccessible</code> to gain access to private
230      * fields. This means that it will throw a security exception if run under
231      * a security manager, if the permissions are not set up correctly. It is also
232      * not as efficient as testing explicitly. Non-primitive fields are compared using 
233      * <code>equals()</code>.</p>
234      * 
235      * <p>Transient members will be not be tested, as they are likely derived
236      * fields, and not part of the value of the Object.</p>
237      *
238      * <p>Static fields will not be tested. Superclass fields will be included.</p>
239      *
240      * @param lhs  <code>this</code> object
241      * @param rhs  the other object
242      * @param excludeFields  Collection of String field names to exclude from testing
243      * @return <code>true</code> if the two Objects have tested equals.
244      * 
245      * @see EqualsExclude
246      */
247     public static boolean reflectionEquals(final Object lhs, final Object rhs, final Collection<String> excludeFields) {
248         return reflectionEquals(lhs, rhs, ReflectionToStringBuilder.toNoNullStringArray(excludeFields));
249     }
250 
251     /**
252      * <p>This method uses reflection to determine if the two <code>Object</code>s
253      * are equal.</p>
254      *
255      * <p>It uses <code>AccessibleObject.setAccessible</code> to gain access to private
256      * fields. This means that it will throw a security exception if run under
257      * a security manager, if the permissions are not set up correctly. It is also
258      * not as efficient as testing explicitly. Non-primitive fields are compared using 
259      * <code>equals()</code>.</p>
260      *
261      * <p>Transient members will be not be tested, as they are likely derived
262      * fields, and not part of the value of the Object.</p>
263      *
264      * <p>Static fields will not be tested. Superclass fields will be included.</p>
265      *
266      * @param lhs  <code>this</code> object
267      * @param rhs  the other object
268      * @param excludeFields  array of field names to exclude from testing
269      * @return <code>true</code> if the two Objects have tested equals.
270      * 
271      * @see EqualsExclude
272      */
273     public static boolean reflectionEquals(final Object lhs, final Object rhs, final String... excludeFields) {
274         return reflectionEquals(lhs, rhs, false, null, excludeFields);
275     }
276 
277     /**
278      * <p>This method uses reflection to determine if the two <code>Object</code>s
279      * are equal.</p>
280      *
281      * <p>It uses <code>AccessibleObject.setAccessible</code> to gain access to private
282      * fields. This means that it will throw a security exception if run under
283      * a security manager, if the permissions are not set up correctly. It is also
284      * not as efficient as testing explicitly. Non-primitive fields are compared using 
285      * <code>equals()</code>.</p>
286      *
287      * <p>If the TestTransients parameter is set to <code>true</code>, transient
288      * members will be tested, otherwise they are ignored, as they are likely
289      * derived fields, and not part of the value of the <code>Object</code>.</p>
290      *
291      * <p>Static fields will not be tested. Superclass fields will be included.</p>
292      *
293      * @param lhs  <code>this</code> object
294      * @param rhs  the other object
295      * @param testTransients  whether to include transient fields
296      * @return <code>true</code> if the two Objects have tested equals.
297      * 
298      * @see EqualsExclude
299      */
300     public static boolean reflectionEquals(final Object lhs, final Object rhs, final boolean testTransients) {
301         return reflectionEquals(lhs, rhs, testTransients, null);
302     }
303 
304     /**
305      * <p>This method uses reflection to determine if the two <code>Object</code>s
306      * are equal.</p>
307      *
308      * <p>It uses <code>AccessibleObject.setAccessible</code> to gain access to private
309      * fields. This means that it will throw a security exception if run under
310      * a security manager, if the permissions are not set up correctly. It is also
311      * not as efficient as testing explicitly. Non-primitive fields are compared using 
312      * <code>equals()</code>.</p>
313      *
314      * <p>If the testTransients parameter is set to <code>true</code>, transient
315      * members will be tested, otherwise they are ignored, as they are likely
316      * derived fields, and not part of the value of the <code>Object</code>.</p>
317      *
318      * <p>Static fields will not be included. Superclass fields will be appended
319      * up to and including the specified superclass. A null superclass is treated
320      * as java.lang.Object.</p>
321      *
322      * @param lhs  <code>this</code> object
323      * @param rhs  the other object
324      * @param testTransients  whether to include transient fields
325      * @param reflectUpToClass  the superclass to reflect up to (inclusive),
326      *  may be <code>null</code>
327      * @param excludeFields  array of field names to exclude from testing
328      * @return <code>true</code> if the two Objects have tested equals.
329      * 
330      * @see EqualsExclude
331      * @since 2.0
332      */
333     public static boolean reflectionEquals(final Object lhs, final Object rhs, final boolean testTransients, final Class<?> reflectUpToClass,
334             final String... excludeFields) {
335         if (lhs == rhs) {
336             return true;
337         }
338         if (lhs == null || rhs == null) {
339             return false;
340         }
341         // Find the leaf class since there may be transients in the leaf
342         // class or in classes between the leaf and root.
343         // If we are not testing transients or a subclass has no ivars,
344         // then a subclass can test equals to a superclass.
345         final Class<?> lhsClass = lhs.getClass();
346         final Class<?> rhsClass = rhs.getClass();
347         Class<?> testClass;
348         if (lhsClass.isInstance(rhs)) {
349             testClass = lhsClass;
350             if (!rhsClass.isInstance(lhs)) {
351                 // rhsClass is a subclass of lhsClass
352                 testClass = rhsClass;
353             }
354         } else if (rhsClass.isInstance(lhs)) {
355             testClass = rhsClass;
356             if (!lhsClass.isInstance(rhs)) {
357                 // lhsClass is a subclass of rhsClass
358                 testClass = lhsClass;
359             }
360         } else {
361             // The two classes are not related.
362             return false;
363         }
364         final EqualsBuilder equalsBuilder = new EqualsBuilder();
365         try {
366             if (testClass.isArray()) {
367                 equalsBuilder.append(lhs, rhs);
368             } else {
369                 reflectionAppend(lhs, rhs, testClass, equalsBuilder, testTransients, excludeFields);
370                 while (testClass.getSuperclass() != null && testClass != reflectUpToClass) {
371                     testClass = testClass.getSuperclass();
372                     reflectionAppend(lhs, rhs, testClass, equalsBuilder, testTransients, excludeFields);
373                 }
374             }
375         } catch (final IllegalArgumentException e) {
376             // In this case, we tried to test a subclass vs. a superclass and
377             // the subclass has ivars or the ivars are transient and
378             // we are testing transients.
379             // If a subclass has ivars that we are trying to test them, we get an
380             // exception and we know that the objects are not equal.
381             return false;
382         }
383         return equalsBuilder.isEquals();
384     }
385 
386     /**
387      * <p>Appends the fields and values defined by the given object of the
388      * given Class.</p>
389      *
390      * @param lhs  the left hand object
391      * @param rhs  the right hand object
392      * @param clazz  the class to append details of
393      * @param builder  the builder to append to
394      * @param useTransients  whether to test transient fields
395      * @param excludeFields  array of field names to exclude from testing
396      */
397     private static void reflectionAppend(
398         final Object lhs,
399         final Object rhs,
400         final Class<?> clazz,
401         final EqualsBuilder builder,
402         final boolean useTransients,
403         final String[] excludeFields) {
404 
405         if (isRegistered(lhs, rhs)) {
406             return;
407         }
408 
409         try {
410             register(lhs, rhs);
411             final Field[] fields = clazz.getDeclaredFields();
412             AccessibleObject.setAccessible(fields, true);
413             for (int i = 0; i < fields.length && builder.isEquals; i++) {
414                 final Field f = fields[i];
415                 if (!ArrayUtils.contains(excludeFields, f.getName())
416                     && !f.getName().contains("$")
417                     && (useTransients || !Modifier.isTransient(f.getModifiers()))
418                     && (!Modifier.isStatic(f.getModifiers()))
419                     && (!f.isAnnotationPresent(EqualsExclude.class))) {
420                     try {
421                         builder.append(f.get(lhs), f.get(rhs));
422                     } catch (final IllegalAccessException e) {
423                         //this can't happen. Would get a Security exception instead
424                         //throw a runtime exception in case the impossible happens.
425                         throw new InternalError("Unexpected IllegalAccessException");
426                     }
427                 }
428             }
429         } finally {
430             unregister(lhs, rhs);
431         }
432     }
433 
434     //-------------------------------------------------------------------------
435 
436     /**
437      * <p>Adds the result of <code>super.equals()</code> to this builder.</p>
438      *
439      * @param superEquals  the result of calling <code>super.equals()</code>
440      * @return EqualsBuilder - used to chain calls.
441      * @since 2.0
442      */
443     public EqualsBuilder appendSuper(final boolean superEquals) {
444         if (!isEquals) {
445             return this;
446         }
447         isEquals = superEquals;
448         return this;
449     }
450 
451     //-------------------------------------------------------------------------
452 
453     /**
454      * <p>Test if two <code>Object</code>s are equal using their
455      * <code>equals</code> method.</p>
456      *
457      * @param lhs  the left hand object
458      * @param rhs  the right hand object
459      * @return EqualsBuilder - used to chain calls.
460      */
461     public EqualsBuilder append(final Object lhs, final Object rhs) {
462         if (!isEquals) {
463             return this;
464         }
465         if (lhs == rhs) {
466             return this;
467         }
468         if (lhs == null || rhs == null) {
469             this.setEquals(false);
470             return this;
471         }
472         final Class<?> lhsClass = lhs.getClass();
473         if (!lhsClass.isArray()) {
474             // The simple case, not an array, just test the element
475             isEquals = lhs.equals(rhs);
476         } else {
477             // factor out array case in order to keep method small enough
478             // to be inlined
479             appendArray(lhs, rhs);
480         }
481         return this;
482     }
483 
484     /**
485      * <p>Test if an <code>Object</code> is equal to an array.</p>
486      *
487      * @param lhs  the left hand object, an array
488      * @param rhs  the right hand object
489      */
490     private void appendArray(final Object lhs, final Object rhs) {
491         if (lhs.getClass() != rhs.getClass()) {
492             // Here when we compare different dimensions, for example: a boolean[][] to a boolean[]
493             this.setEquals(false);
494         }
495         // 'Switch' on type of array, to dispatch to the correct handler
496         // This handles multi dimensional arrays of the same depth
497         else if (lhs instanceof long[]) {
498             append((long[]) lhs, (long[]) rhs);
499         } else if (lhs instanceof int[]) {
500             append((int[]) lhs, (int[]) rhs);
501         } else if (lhs instanceof short[]) {
502             append((short[]) lhs, (short[]) rhs);
503         } else if (lhs instanceof char[]) {
504             append((char[]) lhs, (char[]) rhs);
505         } else if (lhs instanceof byte[]) {
506             append((byte[]) lhs, (byte[]) rhs);
507         } else if (lhs instanceof double[]) {
508             append((double[]) lhs, (double[]) rhs);
509         } else if (lhs instanceof float[]) {
510             append((float[]) lhs, (float[]) rhs);
511         } else if (lhs instanceof boolean[]) {
512             append((boolean[]) lhs, (boolean[]) rhs);
513         } else {
514             // Not an array of primitives
515             append((Object[]) lhs, (Object[]) rhs);
516         }
517     }
518 
519     /**
520      * <p>
521      * Test if two <code>long</code> s are equal.
522      * </p>
523      *
524      * @param lhs
525      *                  the left hand <code>long</code>
526      * @param rhs
527      *                  the right hand <code>long</code>
528      * @return EqualsBuilder - used to chain calls.
529      */
530     public EqualsBuilder append(final long lhs, final long rhs) {
531         if (!isEquals) {
532             return this;
533         }
534         isEquals = lhs == rhs;
535         return this;
536     }
537 
538     /**
539      * <p>Test if two <code>int</code>s are equal.</p>
540      *
541      * @param lhs  the left hand <code>int</code>
542      * @param rhs  the right hand <code>int</code>
543      * @return EqualsBuilder - used to chain calls.
544      */
545     public EqualsBuilder append(final int lhs, final int rhs) {
546         if (!isEquals) {
547             return this;
548         }
549         isEquals = lhs == rhs;
550         return this;
551     }
552 
553     /**
554      * <p>Test if two <code>short</code>s are equal.</p>
555      *
556      * @param lhs  the left hand <code>short</code>
557      * @param rhs  the right hand <code>short</code>
558      * @return EqualsBuilder - used to chain calls.
559      */
560     public EqualsBuilder append(final short lhs, final short rhs) {
561         if (!isEquals) {
562             return this;
563         }
564         isEquals = lhs == rhs;
565         return this;
566     }
567 
568     /**
569      * <p>Test if two <code>char</code>s are equal.</p>
570      *
571      * @param lhs  the left hand <code>char</code>
572      * @param rhs  the right hand <code>char</code>
573      * @return EqualsBuilder - used to chain calls.
574      */
575     public EqualsBuilder append(final char lhs, final char rhs) {
576         if (!isEquals) {
577             return this;
578         }
579         isEquals = lhs == rhs;
580         return this;
581     }
582 
583     /**
584      * <p>Test if two <code>byte</code>s are equal.</p>
585      *
586      * @param lhs  the left hand <code>byte</code>
587      * @param rhs  the right hand <code>byte</code>
588      * @return EqualsBuilder - used to chain calls.
589      */
590     public EqualsBuilder append(final byte lhs, final byte rhs) {
591         if (!isEquals) {
592             return this;
593         }
594         isEquals = lhs == rhs;
595         return this;
596     }
597 
598     /**
599      * <p>Test if two <code>double</code>s are equal by testing that the
600      * pattern of bits returned by <code>doubleToLong</code> are equal.</p>
601      *
602      * <p>This handles NaNs, Infinities, and <code>-0.0</code>.</p>
603      *
604      * <p>It is compatible with the hash code generated by
605      * <code>HashCodeBuilder</code>.</p>
606      *
607      * @param lhs  the left hand <code>double</code>
608      * @param rhs  the right hand <code>double</code>
609      * @return EqualsBuilder - used to chain calls.
610      */
611     public EqualsBuilder append(final double lhs, final double rhs) {
612         if (!isEquals) {
613             return this;
614         }
615         return append(Double.doubleToLongBits(lhs), Double.doubleToLongBits(rhs));
616     }
617 
618     /**
619      * <p>Test if two <code>float</code>s are equal byt testing that the
620      * pattern of bits returned by doubleToLong are equal.</p>
621      *
622      * <p>This handles NaNs, Infinities, and <code>-0.0</code>.</p>
623      *
624      * <p>It is compatible with the hash code generated by
625      * <code>HashCodeBuilder</code>.</p>
626      *
627      * @param lhs  the left hand <code>float</code>
628      * @param rhs  the right hand <code>float</code>
629      * @return EqualsBuilder - used to chain calls.
630      */
631     public EqualsBuilder append(final float lhs, final float rhs) {
632         if (!isEquals) {
633             return this;
634         }
635         return append(Float.floatToIntBits(lhs), Float.floatToIntBits(rhs));
636     }
637 
638     /**
639      * <p>Test if two <code>booleans</code>s are equal.</p>
640      *
641      * @param lhs  the left hand <code>boolean</code>
642      * @param rhs  the right hand <code>boolean</code>
643      * @return EqualsBuilder - used to chain calls.
644       */
645     public EqualsBuilder append(final boolean lhs, final boolean rhs) {
646         if (!isEquals) {
647             return this;
648         }
649         isEquals = lhs == rhs;
650         return this;
651     }
652 
653     /**
654      * <p>Performs a deep comparison of two <code>Object</code> arrays.</p>
655      *
656      * <p>This also will be called for the top level of
657      * multi-dimensional, ragged, and multi-typed arrays.</p>
658      *
659      * @param lhs  the left hand <code>Object[]</code>
660      * @param rhs  the right hand <code>Object[]</code>
661      * @return EqualsBuilder - used to chain calls.
662      */
663     public EqualsBuilder append(final Object[] lhs, final Object[] rhs) {
664         if (!isEquals) {
665             return this;
666         }
667         if (lhs == rhs) {
668             return this;
669         }
670         if (lhs == null || rhs == null) {
671             this.setEquals(false);
672             return this;
673         }
674         if (lhs.length != rhs.length) {
675             this.setEquals(false);
676             return this;
677         }
678         for (int i = 0; i < lhs.length && isEquals; ++i) {
679             append(lhs[i], rhs[i]);
680         }
681         return this;
682     }
683 
684     /**
685      * <p>Deep comparison of array of <code>long</code>. Length and all
686      * values are compared.</p>
687      *
688      * <p>The method {@link #append(long, long)} is used.</p>
689      *
690      * @param lhs  the left hand <code>long[]</code>
691      * @param rhs  the right hand <code>long[]</code>
692      * @return EqualsBuilder - used to chain calls.
693      */
694     public EqualsBuilder append(final long[] lhs, final long[] rhs) {
695         if (!isEquals) {
696             return this;
697         }
698         if (lhs == rhs) {
699             return this;
700         }
701         if (lhs == null || rhs == null) {
702             this.setEquals(false);
703             return this;
704         }
705         if (lhs.length != rhs.length) {
706             this.setEquals(false);
707             return this;
708         }
709         for (int i = 0; i < lhs.length && isEquals; ++i) {
710             append(lhs[i], rhs[i]);
711         }
712         return this;
713     }
714 
715     /**
716      * <p>Deep comparison of array of <code>int</code>. Length and all
717      * values are compared.</p>
718      *
719      * <p>The method {@link #append(int, int)} is used.</p>
720      *
721      * @param lhs  the left hand <code>int[]</code>
722      * @param rhs  the right hand <code>int[]</code>
723      * @return EqualsBuilder - used to chain calls.
724      */
725     public EqualsBuilder append(final int[] lhs, final int[] rhs) {
726         if (!isEquals) {
727             return this;
728         }
729         if (lhs == rhs) {
730             return this;
731         }
732         if (lhs == null || rhs == null) {
733             this.setEquals(false);
734             return this;
735         }
736         if (lhs.length != rhs.length) {
737             this.setEquals(false);
738             return this;
739         }
740         for (int i = 0; i < lhs.length && isEquals; ++i) {
741             append(lhs[i], rhs[i]);
742         }
743         return this;
744     }
745 
746     /**
747      * <p>Deep comparison of array of <code>short</code>. Length and all
748      * values are compared.</p>
749      *
750      * <p>The method {@link #append(short, short)} is used.</p>
751      *
752      * @param lhs  the left hand <code>short[]</code>
753      * @param rhs  the right hand <code>short[]</code>
754      * @return EqualsBuilder - used to chain calls.
755      */
756     public EqualsBuilder append(final short[] lhs, final short[] rhs) {
757         if (!isEquals) {
758             return this;
759         }
760         if (lhs == rhs) {
761             return this;
762         }
763         if (lhs == null || rhs == null) {
764             this.setEquals(false);
765             return this;
766         }
767         if (lhs.length != rhs.length) {
768             this.setEquals(false);
769             return this;
770         }
771         for (int i = 0; i < lhs.length && isEquals; ++i) {
772             append(lhs[i], rhs[i]);
773         }
774         return this;
775     }
776 
777     /**
778      * <p>Deep comparison of array of <code>char</code>. Length and all
779      * values are compared.</p>
780      *
781      * <p>The method {@link #append(char, char)} is used.</p>
782      *
783      * @param lhs  the left hand <code>char[]</code>
784      * @param rhs  the right hand <code>char[]</code>
785      * @return EqualsBuilder - used to chain calls.
786      */
787     public EqualsBuilder append(final char[] lhs, final char[] rhs) {
788         if (!isEquals) {
789             return this;
790         }
791         if (lhs == rhs) {
792             return this;
793         }
794         if (lhs == null || rhs == null) {
795             this.setEquals(false);
796             return this;
797         }
798         if (lhs.length != rhs.length) {
799             this.setEquals(false);
800             return this;
801         }
802         for (int i = 0; i < lhs.length && isEquals; ++i) {
803             append(lhs[i], rhs[i]);
804         }
805         return this;
806     }
807 
808     /**
809      * <p>Deep comparison of array of <code>byte</code>. Length and all
810      * values are compared.</p>
811      *
812      * <p>The method {@link #append(byte, byte)} is used.</p>
813      *
814      * @param lhs  the left hand <code>byte[]</code>
815      * @param rhs  the right hand <code>byte[]</code>
816      * @return EqualsBuilder - used to chain calls.
817      */
818     public EqualsBuilder append(final byte[] lhs, final byte[] rhs) {
819         if (!isEquals) {
820             return this;
821         }
822         if (lhs == rhs) {
823             return this;
824         }
825         if (lhs == null || rhs == null) {
826             this.setEquals(false);
827             return this;
828         }
829         if (lhs.length != rhs.length) {
830             this.setEquals(false);
831             return this;
832         }
833         for (int i = 0; i < lhs.length && isEquals; ++i) {
834             append(lhs[i], rhs[i]);
835         }
836         return this;
837     }
838 
839     /**
840      * <p>Deep comparison of array of <code>double</code>. Length and all
841      * values are compared.</p>
842      *
843      * <p>The method {@link #append(double, double)} is used.</p>
844      *
845      * @param lhs  the left hand <code>double[]</code>
846      * @param rhs  the right hand <code>double[]</code>
847      * @return EqualsBuilder - used to chain calls.
848      */
849     public EqualsBuilder append(final double[] lhs, final double[] rhs) {
850         if (!isEquals) {
851             return this;
852         }
853         if (lhs == rhs) {
854             return this;
855         }
856         if (lhs == null || rhs == null) {
857             this.setEquals(false);
858             return this;
859         }
860         if (lhs.length != rhs.length) {
861             this.setEquals(false);
862             return this;
863         }
864         for (int i = 0; i < lhs.length && isEquals; ++i) {
865             append(lhs[i], rhs[i]);
866         }
867         return this;
868     }
869 
870     /**
871      * <p>Deep comparison of array of <code>float</code>. Length and all
872      * values are compared.</p>
873      *
874      * <p>The method {@link #append(float, float)} is used.</p>
875      *
876      * @param lhs  the left hand <code>float[]</code>
877      * @param rhs  the right hand <code>float[]</code>
878      * @return EqualsBuilder - used to chain calls.
879      */
880     public EqualsBuilder append(final float[] lhs, final float[] rhs) {
881         if (!isEquals) {
882             return this;
883         }
884         if (lhs == rhs) {
885             return this;
886         }
887         if (lhs == null || rhs == null) {
888             this.setEquals(false);
889             return this;
890         }
891         if (lhs.length != rhs.length) {
892             this.setEquals(false);
893             return this;
894         }
895         for (int i = 0; i < lhs.length && isEquals; ++i) {
896             append(lhs[i], rhs[i]);
897         }
898         return this;
899     }
900 
901     /**
902      * <p>Deep comparison of array of <code>boolean</code>. Length and all
903      * values are compared.</p>
904      *
905      * <p>The method {@link #append(boolean, boolean)} is used.</p>
906      *
907      * @param lhs  the left hand <code>boolean[]</code>
908      * @param rhs  the right hand <code>boolean[]</code>
909      * @return EqualsBuilder - used to chain calls.
910      */
911     public EqualsBuilder append(final boolean[] lhs, final boolean[] rhs) {
912         if (!isEquals) {
913             return this;
914         }
915         if (lhs == rhs) {
916             return this;
917         }
918         if (lhs == null || rhs == null) {
919             this.setEquals(false);
920             return this;
921         }
922         if (lhs.length != rhs.length) {
923             this.setEquals(false);
924             return this;
925         }
926         for (int i = 0; i < lhs.length && isEquals; ++i) {
927             append(lhs[i], rhs[i]);
928         }
929         return this;
930     }
931 
932     /**
933      * <p>Returns <code>true</code> if the fields that have been checked
934      * are all equal.</p>
935      *
936      * @return boolean
937      */
938     public boolean isEquals() {
939         return this.isEquals;
940     }
941 
942     /**
943      * <p>Returns <code>true</code> if the fields that have been checked
944      * are all equal.</p>
945      *
946      * @return <code>true</code> if all of the fields that have been checked
947      *         are equal, <code>false</code> otherwise.
948      *
949      * @since 3.0
950      */
951     @Override
952     public Boolean build() {
953         return Boolean.valueOf(isEquals());
954     }
955 
956     /**
957      * Sets the <code>isEquals</code> value.
958      *
959      * @param isEquals The value to set.
960      * @since 2.1
961      */
962     protected void setEquals(final boolean isEquals) {
963         this.isEquals = isEquals;
964     }
965 
966     /**
967      * Reset the EqualsBuilder so you can use the same object again
968      * @since 2.5
969      */
970     public void reset() {
971         this.isEquals = true;
972     }
973 }