testiteratorutils.java

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/*
 *  Copyright 2001-2004 The Apache Software Foundation
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */
package org.apache.commons.collections;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
import java.util.ListIterator;
import java.util.NoSuchElementException;

import junit.framework.Test;

import org.apache.commons.collections.iterators.EmptyIterator;
import org.apache.commons.collections.iterators.EmptyListIterator;
import org.apache.commons.collections.iterators.EmptyMapIterator;
import org.apache.commons.collections.iterators.EmptyOrderedIterator;
import org.apache.commons.collections.iterators.EmptyOrderedMapIterator;

/**
 * Tests for IteratorUtils.
 * 
 * @version $Revision: 155406 $ $Date: 2005-02-26 12:55:26 +0000 (Sat, 26 Feb 2005) $
 * 
 * @author Unknown
 */
public class TestIteratorUtils extends BulkTest {

    public TestIteratorUtils(String name) {
        super(name);
    }

    public static void main(String args[]) {
        junit.textui.TestRunner.run(suite());
    }

    public static Test suite() {
        return BulkTest.makeSuite(TestIteratorUtils.class);
    }

    public void testToList() {
        List list = new ArrayList();
        list.add(new Integer(1));
        list.add("Two");
        list.add(null);
        List result = IteratorUtils.toList(list.iterator());
        assertEquals(list, result);
    }

    public void testToArray() {
        List list = new ArrayList();
        list.add(new Integer(1));
        list.add("Two");
        list.add(null);
        Object[] result = IteratorUtils.toArray(list.iterator());
        assertEquals(list, Arrays.asList(result));
    }

    public void testToArray2() {
        List list = new ArrayList();
        list.add("One");
        list.add("Two");
        list.add(null);
        String[] result = (String[]) IteratorUtils.toArray(list.iterator(), String.class);
        assertEquals(list, Arrays.asList(result));
    }
    
    public void testArrayIterator() {
        Object[] objArray = {"a", "b", "c"};
        ResettableIterator iterator = IteratorUtils.arrayIterator(objArray);
        assertTrue(iterator.next().equals("a"));
        assertTrue(iterator.next().equals("b"));
        iterator.reset();
        assertTrue(iterator.next().equals("a"));
        
        try {
            iterator = IteratorUtils.arrayIterator(new Integer(0));
            fail("Expecting IllegalArgumentException");
        } catch (IllegalArgumentException ex) {
                // expected
        }
        
        try {
            iterator = IteratorUtils.arrayIterator(null);
            fail("Expecting NullPointerException");
        } catch (NullPointerException ex) {
                // expected
        }
        
        iterator = IteratorUtils.arrayIterator(objArray, 1);
        assertTrue(iterator.next().equals("b"));
        
        try {
            iterator = IteratorUtils.arrayIterator(objArray, -1);
            fail("Expecting IndexOutOfBoundsException");
        } catch (IndexOutOfBoundsException ex) {
            // expected
        }
        
        iterator = IteratorUtils.arrayIterator(objArray, 3);
        assertTrue(!iterator.hasNext());
        iterator.reset();
        
        try {
            iterator = IteratorUtils.arrayIterator(objArray, 4);
            fail("Expecting IndexOutOfBoundsException");
        } catch (IndexOutOfBoundsException ex) {
            // expected
        }
        
        iterator = IteratorUtils.arrayIterator(objArray, 2, 3);
        assertTrue(iterator.next().equals("c"));
        
        try {
            iterator = IteratorUtils.arrayIterator(objArray, 2, 4);
            fail("Expecting IndexOutOfBoundsException");
        } catch (IndexOutOfBoundsException ex) {
            // expected
        }
        
        try {
            iterator = IteratorUtils.arrayIterator(objArray, -1, 1);
            fail("Expecting IndexOutOfBoundsException");
        } catch (IndexOutOfBoundsException ex) {
            // expected
        }
        
        try {
            iterator = IteratorUtils.arrayIterator(objArray, 2, 1);
            fail("Expecting IllegalArgumentException");
        } catch (IllegalArgumentException ex) {
            // expected
        }
        
        int[] intArray = {0, 1, 2};
        iterator = IteratorUtils.arrayIterator(intArray);
        assertTrue(iterator.next().equals(new Integer(0)));
        assertTrue(iterator.next().equals(new Integer(1)));
        iterator.reset();
        assertTrue(iterator.next().equals(new Integer(0)));
        
        iterator = IteratorUtils.arrayIterator(intArray, 1);
        assertTrue(iterator.next().equals(new Integer(1)));
        
        try {
            iterator = IteratorUtils.arrayIterator(intArray, -1);
            fail("Expecting IndexOutOfBoundsException");
        } catch (IndexOutOfBoundsException ex) {
            // expected
        }
        
        iterator = IteratorUtils.arrayIterator(intArray, 3);
        assertTrue(!iterator.hasNext());
        iterator.reset();
        
        try {
            iterator = IteratorUtils.arrayIterator(intArray, 4);
            fail("Expecting IndexOutOfBoundsException");
        } catch (IndexOutOfBoundsException ex) {
            // expected
        }
        
        iterator = IteratorUtils.arrayIterator(intArray, 2, 3);
        assertTrue(iterator.next().equals(new Integer(2)));
        
        try {
            iterator = IteratorUtils.arrayIterator(intArray, 2, 4);
            fail("Expecting IndexOutOfBoundsException");
        } catch (IndexOutOfBoundsException ex) {
            // expected
        }
        
        try {
            iterator = IteratorUtils.arrayIterator(intArray, -1, 1);
            fail("Expecting IndexOutOfBoundsException");
        } catch (IndexOutOfBoundsException ex) {
            // expected
        }
        
        try {
            iterator = IteratorUtils.arrayIterator(intArray, 2, 1);
            fail("Expecting IllegalArgumentException");
        } catch (IllegalArgumentException ex) {
            // expected
        }          
    }
    
    public void testArrayListIterator() {
        Object[] objArray = {"a", "b", "c", "d"};
        ResettableListIterator iterator = IteratorUtils.arrayListIterator(objArray);
        assertTrue(!iterator.hasPrevious());
        assertTrue(iterator.previousIndex() == -1);
        assertTrue(iterator.nextIndex() == 0);
        assertTrue(iterator.next().equals("a"));
        assertTrue(iterator.previous().equals("a"));
        assertTrue(iterator.next().equals("a"));
        assertTrue(iterator.previousIndex() == 0);
        assertTrue(iterator.nextIndex() == 1);
        assertTrue(iterator.next().equals("b"));
        assertTrue(iterator.next().equals("c"));
        assertTrue(iterator.next().equals("d"));
        assertTrue(iterator.nextIndex() == 4); // size of list
        assertTrue(iterator.previousIndex() == 3);
        
        try {
            iterator = IteratorUtils.arrayListIterator(new Integer(0));
            fail("Expecting IllegalArgumentException");
        } catch (IllegalArgumentException ex) {
                // expected
        }
        
        try {
            iterator = IteratorUtils.arrayListIterator(null);
            fail("Expecting NullPointerException");
        } catch (NullPointerException ex) {
                // expected
        }
        
        iterator = IteratorUtils.arrayListIterator(objArray, 1);
        assertTrue(iterator.previousIndex() == -1); 
        assertTrue(!iterator.hasPrevious());
        assertTrue(iterator.nextIndex() == 0); 
        assertTrue(iterator.next().equals("b"));
        assertTrue(iterator.previousIndex() == 0);        
        
        try {
            iterator = IteratorUtils.arrayListIterator(objArray, -1);
            fail("Expecting IndexOutOfBoundsException.");
        } catch (IndexOutOfBoundsException ex) {
            // expected
        }
        
        iterator = IteratorUtils.arrayListIterator(objArray, 3);
        assertTrue(iterator.hasNext());
        try {
            Object x = iterator.previous();
            fail("Expecting NoSuchElementException.");
        } catch (NoSuchElementException ex) {
            // expected
        }
        
        try {
            iterator = IteratorUtils.arrayListIterator(objArray, 5);
            fail("Expecting IndexOutOfBoundsException.");
        } catch (IndexOutOfBoundsException ex) {
            // expected
        }
        
        iterator = IteratorUtils.arrayListIterator(objArray, 2, 3);
        assertTrue(iterator.next().equals("c"));
        
        try {
            iterator = IteratorUtils.arrayListIterator(objArray, 2, 5);
            fail("Expecting IndexOutOfBoundsException");
        } catch (IndexOutOfBoundsException ex) {
            // expected
        }
        
        try {
            iterator = IteratorUtils.arrayListIterator(objArray, -1, 1);
            fail("Expecting IndexOutOfBoundsException");
        } catch (IndexOutOfBoundsException ex) {
            // expected
        }
        
        try {
            iterator = IteratorUtils.arrayListIterator(objArray, 2, 1);
            fail("Expecting IllegalArgumentException");
        } catch (IllegalArgumentException ex) {
            // expected
        }
        
        int[] intArray = {0, 1, 2};
        iterator = IteratorUtils.arrayListIterator(intArray);
        assertTrue(iterator.previousIndex() == -1); 
        assertTrue(!iterator.hasPrevious());
        assertTrue(iterator.nextIndex() == 0); 
        assertTrue(iterator.next().equals(new Integer(0)));
        assertTrue(iterator.previousIndex() == 0); 
        assertTrue(iterator.nextIndex() == 1); 
        assertTrue(iterator.next().equals(new Integer(1)));
        assertTrue(iterator.previousIndex() == 1); 
        assertTrue(iterator.nextIndex() == 2); 
        assertTrue(iterator.previous().equals(new Integer(1)));
        assertTrue(iterator.next().equals(new Integer(1)));
        
        iterator = IteratorUtils.arrayListIterator(intArray, 1);
        assertTrue(iterator.previousIndex() == -1); 
        assertTrue(!iterator.hasPrevious());
        assertTrue(iterator.nextIndex() == 0); 
        assertTrue(iterator.next().equals(new Integer(1)));
        assertTrue(iterator.previous().equals(new Integer(1)));
        assertTrue(iterator.next().equals(new Integer(1)));
        assertTrue(iterator.previousIndex() == 0); 
        assertTrue(iterator.nextIndex() == 1); 
        assertTrue(iterator.next().equals(new Integer(2)));
        assertTrue(iterator.previousIndex() == 1); 
        assertTrue(iterator.nextIndex() == 2); 
        assertTrue(iterator.previous().equals(new Integer(2)));
        assertTrue(iterator.previousIndex() == 0); 
        assertTrue(iterator.nextIndex() == 1); 
        
        try {
            iterator = IteratorUtils.arrayListIterator(intArray, -1);
            fail("Expecting IndexOutOfBoundsException");
        } catch (IndexOutOfBoundsException ex) {
            // expected
        }
        
        iterator = IteratorUtils.arrayListIterator(intArray, 3);
        assertTrue(!iterator.hasNext());
     
        try {
            iterator = IteratorUtils.arrayListIterator(intArray, 4);
            fail("Expecting IndexOutOfBoundsException");
        } catch (IndexOutOfBoundsException ex) {
            // expected
        }
        
        iterator = IteratorUtils.arrayListIterator(intArray, 2, 3);
        assertTrue(!iterator.hasPrevious());
        assertTrue(iterator.previousIndex() == -1);
        assertTrue(iterator.next().equals(new Integer(2)));
        assertTrue(iterator.hasPrevious());
        assertTrue(!iterator.hasNext());
        
        
        try {
            iterator = IteratorUtils.arrayListIterator(intArray, 2, 4);
            fail("Expecting IndexOutOfBoundsException");
        } catch (IndexOutOfBoundsException ex) {
            // expected
        }
        
        try {
            iterator = IteratorUtils.arrayListIterator(intArray, -1, 1);
            fail("Expecting IndexOutOfBoundsException");
        } catch (IndexOutOfBoundsException ex) {
            // expected
        }
        
        try {
            iterator = IteratorUtils.arrayListIterator(intArray, 2, 1);
            fail("Expecting IllegalArgumentException");
        } catch (IllegalArgumentException ex) {
            // expected
        }          
    }