1 /*
2 * Copyright (c) 2002, 2026, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24 /*
25 * @test
26 * @bug 4726380 8037097
27 * @summary Check that different sorts give equivalent results.
28 * @key randomness
29 * @run junit Correct
30 */
31
32 import java.util.*;
33
34 import org.junit.jupiter.api.Assertions;
35 import org.junit.jupiter.api.Test;
36 import org.junit.jupiter.api.TestInstance;
37 import org.junit.jupiter.params.ParameterizedTest;
38 import org.junit.jupiter.params.provider.MethodSource;
39
40 @TestInstance(TestInstance.Lifecycle.PER_CLASS)
41 public class Correct {
42
43 static final Random rnd = new Random();
44 static final int ITERATIONS = 1000;
45 static final int TEST_SIZE = 1000;
46
47 @Test
48 public void testDefaultSort() {
49 for (int i=0; i<ITERATIONS; i++) {
50 int size = rnd.nextInt(TEST_SIZE) + 1;
51 Integer[] array1 = getIntegerArray(size);
52 Integer[] array2 = Arrays.copyOf(array1, array1.length);
53 Arrays.sort(array1, array1.length/3, array1.length/2);
54 stupidSort(array2, array2.length/3, array2.length/2);
55 Assertions.assertArrayEquals(array2, array1, "Arrays did not match. size=" + size);
56 }
57 }
58
59 @ParameterizedTest
60 @MethodSource("comparators")
61 public void testComparatorSort(Comparator<Integer> comparator) {
62 for (int i=0; i<ITERATIONS; i++) {
63 int size = rnd.nextInt(TEST_SIZE) + 1;
64 Integer[] array1 = getIntegerArray(size);
65 Integer[] array2 = Arrays.copyOf(array1, array1.length);
66 Arrays.sort(array1, array1.length/3, array1.length/2, comparator);
67 stupidSort(array2, array2.length/3, array2.length/2, comparator);
68 Assertions.assertArrayEquals(array2, array1, "Arrays did not match. size=" + size);
69 }
70 }
71
72 static Integer[] getIntegerArray(int size) {
73 Integer[] blah = new Integer[size];
74 for (int x=0; x<size; x++) {
75 blah[x] = new Integer(rnd.nextInt());
76 }
77 return blah;
78 }
79
80 static void stupidSort(Integer[] a1, int from, int to) {
81 if (from > to - 1 )
82 return;
83
84 for (int x=from; x<to; x++) {
85 Integer lowest = a1[x];
86 int lowestIndex = x;
87 for (int y=x + 1; y<to; y++) {
88 if (((Comparable)a1[y]).compareTo((Comparable)lowest) < 0) {
89 lowest = a1[y];
90 lowestIndex = y;
91 }
92 }
93 if (lowestIndex != x) {
94 swap(a1, x, lowestIndex);
95 }
96 }
97 }
98
99 static void stupidSort(Integer[] a1, int from, int to, Comparator<Integer> comparator) {
100 if (from > to - 1 )
101 return;
102
103 for (int x=from; x<to; x++) {
104 Integer lowest = a1[x];
105 int lowestIndex = x;
106 for (int y=x + 1; y<to; y++) {
107 if (comparator.compare(a1[y], lowest) < 0) {
108 lowest = a1[y];
109 lowestIndex = y;
110 }
111 }
112 if (lowestIndex != x) {
113 swap(a1, x, lowestIndex);
114 }
115 }
116 }
117
118 static <T> void swap(T[] x, int a, int b) {
119 T t = x[a];
120 x[a] = x[b];
121 x[b] = t;
122 }
123
124 public static Iterator<Object[]> comparators() {
125 Object[][] comparators = new Object[][] {
126 new Object[] { Comparator.naturalOrder() },
127 new Object[] { Comparator.<Integer>naturalOrder().reversed() },
128 new Object[] { STANDARD_ORDER },
129 new Object[] { STANDARD_ORDER.reversed() },
130 new Object[] { REVERSE_ORDER },
131 new Object[] { REVERSE_ORDER.reversed() },
132 new Object[] { Comparator.comparingInt(Integer::intValue) }
133 };
134
135 return Arrays.asList(comparators).iterator();
136 }
137
138 private static final Comparator<Integer> STANDARD_ORDER = new Comparator<Integer>() {
139 public int compare(Integer o1, Integer o2) {
140 return o1.compareTo(o2);
141 }
142 };
143
144 private static final Comparator<Integer> REVERSE_ORDER = new Comparator<Integer>() {
145 public int compare(Integer o1, Integer o2) {
146 return - o1.compareTo(o2);
147 }
148 };
149 }