BubbleSortTest.java

/**
 * Copyright (c) 2004-2011 QOS.ch
 * All rights reserved.
 *
 * Permission is hereby granted, free  of charge, to any person obtaining
 * a  copy  of this  software  and  associated  documentation files  (the
 * "Software"), to  deal in  the Software without  restriction, including
 * without limitation  the rights to  use, copy, modify,  merge, publish,
 * distribute,  sublicense, and/or sell  copies of  the Software,  and to
 * permit persons to whom the Software  is furnished to do so, subject to
 * the following conditions:
 *
 * The  above  copyright  notice  and  this permission  notice  shall  be
 * included in all copies or substantial portions of the Software.
 *
 * THE  SOFTWARE IS  PROVIDED  "AS  IS", WITHOUT  WARRANTY  OF ANY  KIND,
 * EXPRESS OR  IMPLIED, INCLUDING  BUT NOT LIMITED  TO THE  WARRANTIES OF
 * MERCHANTABILITY,    FITNESS    FOR    A   PARTICULAR    PURPOSE    AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
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package org.slf4j.helpers;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;

import java.util.Arrays;
import java.util.Random;

import org.junit.Test;

/**
 * Test that our BubbleSort algorithm is correctly implemented.
 * 
 * @author Ceki
 *
 */
public class BubbleSortTest {

    @Test
    public void testSmoke() {
        int[] a = new int[] { 5, 3, 2, 7 };
        BubbleSort.sort(a);
        int i = 0;
        assertEquals(2, a[i++]);
        assertEquals(3, a[i++]);
        assertEquals(5, a[i++]);
        assertEquals(7, a[i++]);
    }

    @Test
    public void testEmpty() {
        int[] a = new int[] {};
        BubbleSort.sort(a);
    }

    @Test
    public void testSorted() {
        int[] a = new int[] { 3, 30, 300, 3000 };
        BubbleSort.sort(a);
        int i = 0;
        assertEquals(3, a[i++]);
        assertEquals(30, a[i++]);
        assertEquals(300, a[i++]);
        assertEquals(3000, a[i++]);
    }

    @Test
    public void testInverted() {
        int[] a = new int[] { 3000, 300, 30, 3 };
        BubbleSort.sort(a);
        int i = 0;
        assertEquals(3, a[i++]);
        assertEquals(30, a[i++]);
        assertEquals(300, a[i++]);
        assertEquals(3000, a[i++]);
    }

    @Test
    public void testWithSameEntry() {
        int[] a = new int[] { 10, 20, 10, 20 };
        BubbleSort.sort(a);
        int i = 0;
        assertEquals(10, a[i++]);
        assertEquals(10, a[i++]);
        assertEquals(20, a[i++]);
        assertEquals(20, a[i++]);
    }

    @Test
    public void testRandom() {
        int len = 100;
        Random random = new Random(156);
        int[] a = new int[len];
        int[] witness = new int[len];
        for (int i = 0; i < len; i++) {
            int r = random.nextInt();
            a[i] = r;
            witness[i] = r;
        }
        BubbleSort.sort(a);
        Arrays.sort(witness);
        assertTrue(Arrays.equals(witness, a));
    }

}