ArraysTest.java

/*******************************************************************************
 * Copyright (c) 2012-2017 Codenvy, S.A.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *   Codenvy, S.A. - initial API and implementation
 *******************************************************************************/
package org.eclipse.che.ide.util;

import org.junit.Assert;
import org.junit.Test;

/**
 * Unit tests for the {@link Arrays}.
 *
 * @author Vlad Zhukovskyi
 */
public class ArraysTest {

    private static final Object O1 = new Object();
    private static final Object O2 = new Object();
    private static final Object O3 = new Object();

    @Test
    public void arrayShouldCheckForEmptiness() throws Exception {
        Assert.assertTrue(Arrays.isNullOrEmpty(new Object[]{}));
        Assert.assertTrue(Arrays.isNullOrEmpty(null));
    }

    @Test
    public void shouldCheckAddOperations() throws Exception {
        final Object[] arr1 = new Object[]{O1, O2};
        final Object[] arr2 = Arrays.add(arr1, O3);

        Assert.assertTrue(arr1.length == 2);
        Assert.assertTrue(arr2.length == 3);
        Assert.assertTrue(arr1 != arr2);
    }

    @Test(expected = IllegalArgumentException.class)
    public void shouldCheckFailedAddOperations() throws Exception {
        Arrays.add(null, new Object());
    }

    @Test
    public void shouldCheckContainsOperation() throws Exception {
        final Object[] arr1 = new Object[]{O1, O2};

        Assert.assertTrue(Arrays.contains(arr1, O1));
        Assert.assertTrue(Arrays.contains(arr1, O2));
        Assert.assertFalse(Arrays.contains(arr1, O3));
    }

    @Test(expected = IllegalArgumentException.class)
    public void shouldCheckFailedContainsOperations() throws Exception {
        Arrays.contains(null, new Object());
    }

    @Test
    public void shouldCheckIndexOfOperations() throws Exception {
        final Object[] arr1 = new Object[]{O1, O2};

        Assert.assertTrue(Arrays.indexOf(arr1, O1) == 0);
        Assert.assertTrue(Arrays.indexOf(arr1, O2) == 1);
        Assert.assertTrue(Arrays.indexOf(arr1, O3) == -1);
    }

    @Test(expected = IllegalArgumentException.class)
    public void shouldCheckFailedIndexOfOperations() throws Exception {
        Arrays.indexOf(null, new Object());
    }

    @Test
    public void shouldCheckRemoveOperations() throws Exception {
        final Object[] arr1 = new Object[]{O1, O2, O3};
        final Object[] arr2 = Arrays.remove(arr1, O3);

        Assert.assertTrue(arr1.length == 3);
        Assert.assertTrue(arr2.length == 2);
        Assert.assertTrue(arr1 != arr2);
    }

    @Test(expected = IllegalArgumentException.class)
    public void shouldCheckFailedRemoveOperations() throws Exception {
        Arrays.remove(null, new Object());
    }

    @Test
    public void shouldCheckRetainOperations() throws Exception {
        final Object[] arr1 = new Object[]{O1, O2};
        final Object[] arr2 = new Object[]{O2, O3};

        final Object[] result = Arrays.removeAll(arr1, arr2, true);

        Assert.assertTrue(result.length == 1);
        Assert.assertTrue(Arrays.indexOf(result, O1) == -1);
        Assert.assertTrue(Arrays.indexOf(result, O2) == 0);
        Assert.assertTrue(Arrays.indexOf(result, O3) == -1);
    }

    @Test
    public void shouldCheckRemoveAllOperations() throws Exception {
        final Object[] arr1 = new Object[]{O1, O2};
        final Object[] arr2 = new Object[]{O2, O3};

        final Object[] result = Arrays.removeAll(arr1, arr2, false);

        Assert.assertTrue(result.length == 1);
        Assert.assertTrue(Arrays.indexOf(result, O1) == 0);
        Assert.assertTrue(Arrays.indexOf(result, O2) == -1);
        Assert.assertTrue(Arrays.indexOf(result, O3) == -1);
    }

    @Test(expected = IllegalArgumentException.class)
    public void shouldCheckFailedRetainOperations() throws Exception {
        Arrays.removeAll(null, null, false);
    }
}