1 /*
   2  * Copyright (c) 2011, 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 /* @test
  25  * @summary Test MergeSort
  26  *
  27  * @library /src/sample/share/forkjoin/mergesort
  28  * @build MergeSortTest MergeDemo MergeSort
  29  * @run testng MergeSortTest
  30  */
  31 
  32 import java.util.Arrays;
  33 import java.util.Random;
  34 
  35 import org.testng.annotations.Test;
  36 
  37 public class MergeSortTest {
  38     private Random random;
  39     private MergeSort target;
  40 
  41     public MergeSortTest(Random random, MergeSort target) {
  42         this.random = random;
  43         this.target = target;
  44     }
  45 
  46     @Test
  47     public static void doTest() {
  48         MergeSortTest test = new MergeSortTest(new Random(), new MergeSort(Runtime.getRuntime().availableProcessors() * 4));
  49         test.run();
  50     }
  51 
  52     private int[] generateArray(int elements) {
  53         int[] array = new int[elements];
  54         for (int i = 0; i < array.length; ++i) {
  55             array[i] = random.nextInt(10);
  56         }
  57         return array;
  58     }
  59 
  60     private void run() {
  61         testSort();
  62         testSortSingle();
  63         testSortEmpty();
  64         testLong();
  65     }
  66 
  67     public void testLong() {
  68         for (int i = 0; i < 1000; ++i) {
  69             int elements = 1 + i * 100;
  70 
  71             int[] array = generateArray(elements);
  72             int[] copy = Arrays.copyOf(array, array.length);
  73             Arrays.sort(copy);
  74             target.sort(array);
  75             assertEqual(copy, array);
  76         }
  77    }
  78 
  79     private void testSortEmpty() {
  80         int[] array = { };
  81         target.sort(array);
  82         assertEqual(new int[] { }, array);
  83     }
  84 
  85     private void testSortSingle() {
  86         int[] array = { 1 };
  87         target.sort(array);
  88         assertEqual(new int[] { 1 }, array);
  89     }
  90 
  91     private void testSort() {
  92         int[] array = { 7, 3, 9, 0, -6, 12, 54, 3, -6, 88, 1412};
  93         target.sort(array);
  94         assertEqual(new int[] { -6, -6, 0, 3, 3, 7, 9, 12, 54, 88, 1412 }, array);
  95     }
  96 
  97     private void assertEqual(int[] expected, int[] array) {
  98         if (!Arrays.equals(expected, array)) {
  99             throw new RuntimeException("Invalid sorted array!");
 100         }
 101     }
 102 
 103 
 104 }