ListOrderedSetTest.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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
 *
 *      https://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.collections4.set;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertSame;
import static org.junit.jupiter.api.Assertions.assertThrows;
import static org.junit.jupiter.api.Assertions.assertTrue;

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Set;

import org.apache.commons.collections4.IteratorUtils;
import org.junit.jupiter.api.Test;

/**
 * Extension of {@link AbstractSetTest} for exercising the
 * {@link ListOrderedSet} implementation.
 */
public class ListOrderedSetTest<E>
    extends AbstractSetTest<E> {

    static class A {

        @Override
        public boolean equals(final Object obj) {
            return obj instanceof A || obj instanceof B;
        }

        @Override
        public int hashCode() {
            return 1;
        }
    }

    static class B {

        @Override
        public boolean equals(final Object obj) {
            return obj instanceof A || obj instanceof B;
        }

        @Override
        public int hashCode() {
            return 1;
        }
    }

    private static final Integer ZERO = Integer.valueOf(0);

    private static final Integer ONE = Integer.valueOf(1);

    private static final Integer TWO = Integer.valueOf(2);

    private static final Integer THREE = Integer.valueOf(3);

    @Override
    public String getCompatibilityVersion() {
        return "4";
    }

    @Override
    public ListOrderedSet<E> makeObject() {
        return ListOrderedSet.listOrderedSet(new HashSet<>());
    }

    @SuppressWarnings("unchecked")
    protected ListOrderedSet<E> setupSet() {
        final ListOrderedSet<E> set = makeObject();

        for (int i = 0; i < 10; i++) {
            set.add((E) Integer.toString(i));
        }
        return set;
    }

    @Test
    void testDecorator() {
        assertThrows(NullPointerException.class, () -> ListOrderedSet.listOrderedSet((List<E>) null));
        assertThrows(NullPointerException.class, () -> ListOrderedSet.listOrderedSet((Set<E>) null));
        assertThrows(NullPointerException.class, () -> ListOrderedSet.listOrderedSet(null, null));
        assertThrows(NullPointerException.class, () -> ListOrderedSet.listOrderedSet(new HashSet<>(), null));
        assertThrows(NullPointerException.class, () -> ListOrderedSet.listOrderedSet(null, new ArrayList<>()));
    }

    @Test
    @SuppressWarnings("unchecked")
    void testDuplicates() {
        final List<E> list = new ArrayList<>(10);
        list.add((E) Integer.valueOf(1));
        list.add((E) Integer.valueOf(2));
        list.add((E) Integer.valueOf(3));
        list.add((E) Integer.valueOf(1));

        final ListOrderedSet<E> orderedSet = ListOrderedSet.listOrderedSet(list);

        assertEquals(3, orderedSet.size());
        assertEquals(3, IteratorUtils.toArray(orderedSet.iterator()).length);

        // insertion order preserved?
        assertEquals(Integer.valueOf(1), orderedSet.get(0));
        assertEquals(Integer.valueOf(2), orderedSet.get(1));
        assertEquals(Integer.valueOf(3), orderedSet.get(2));
    }

    @Test
    @SuppressWarnings("unchecked")
    void testListAddIndexed() {
        final ListOrderedSet<E> set = makeObject();
        set.add((E) ZERO);
        set.add((E) TWO);

        set.add(1, (E) ONE);
        assertEquals(3, set.size());
        assertSame(ZERO, set.get(0));
        assertSame(ONE, set.get(1));
        assertSame(TWO, set.get(2));

        set.add(0, (E) ONE);
        assertEquals(3, set.size());
        assertSame(ZERO, set.get(0));
        assertSame(ONE, set.get(1));
        assertSame(TWO, set.get(2));

        final List<E> list = new ArrayList<>();
        list.add((E) ZERO);
        list.add((E) TWO);

        set.addAll(0, list);
        assertEquals(3, set.size());
        assertSame(ZERO, set.get(0));
        assertSame(ONE, set.get(1));
        assertSame(TWO, set.get(2));

        list.add(0, (E) THREE); // list = [3,0,2]
        set.remove(TWO); //  set = [0,1]
        set.addAll(1, list);
        assertEquals(4, set.size());
        assertSame(ZERO, set.get(0));
        assertSame(THREE, set.get(1));
        assertSame(TWO, set.get(2));
        assertSame(ONE, set.get(3));
    }

    @Test
    @SuppressWarnings("unchecked")
    void testListAddRemove() {
        final ListOrderedSet<E> set = makeObject();
        final List<E> view = set.asList();
        set.add((E) ZERO);
        set.add((E) ONE);
        set.add((E) TWO);

        assertEquals(3, set.size());
        assertSame(ZERO, set.get(0));
        assertSame(ONE, set.get(1));
        assertSame(TWO, set.get(2));
        assertEquals(3, view.size());
        assertSame(ZERO, view.get(0));
        assertSame(ONE, view.get(1));
        assertSame(TWO, view.get(2));

        assertEquals(0, set.indexOf(ZERO));
        assertEquals(1, set.indexOf(ONE));
        assertEquals(2, set.indexOf(TWO));

        set.remove(1);
        assertEquals(2, set.size());
        assertSame(ZERO, set.get(0));
        assertSame(TWO, set.get(1));
        assertEquals(2, view.size());
        assertSame(ZERO, view.get(0));
        assertSame(TWO, view.get(1));
    }

    @Test
    @SuppressWarnings("unchecked")
    void testListAddReplacing() {
        final ListOrderedSet<E> set = makeObject();
        final A a = new A();
        final B b = new B();
        set.add((E) a);
        assertEquals(1, set.size());
        set.add((E) b); // will match but not replace A as equal
        assertEquals(1, set.size());
        assertSame(a, set.decorated().iterator().next());
        assertSame(a, set.iterator().next());
        assertSame(a, set.get(0));
        assertSame(a, set.asList().get(0));
    }

    @Test
    @SuppressWarnings("unchecked")
    void testOrdering() {
        final ListOrderedSet<E> set = setupSet();
        Iterator<E> it = set.iterator();

        for (int i = 0; i < 10; i++) {
            assertEquals(Integer.toString(i), it.next(), "Sequence is wrong");
        }

        for (int i = 0; i < 10; i += 2) {
            assertTrue(set.remove(Integer.toString(i)),
                       "Must be able to remove int");
        }

        it = set.iterator();
        for (int i = 1; i < 10; i += 2) {
            assertEquals(Integer.toString(i), it.next(),
                         "Sequence is wrong after remove ");
        }

        for (int i = 0; i < 10; i++) {
            set.add((E) Integer.toString(i));
        }

        assertEquals(10, set.size(), "Size of set is wrong!");

        it = set.iterator();
        for (int i = 1; i < 10; i += 2) {
            assertEquals(Integer.toString(i), it.next(), "Sequence is wrong");
        }
        for (int i = 0; i < 10; i += 2) {
            assertEquals(Integer.toString(i), it.next(), "Sequence is wrong");
        }
    }

    @Test
    @SuppressWarnings("unchecked")
    void testRetainAll() {
        final List<E> list = new ArrayList<>(10);
        final Set<E> set = new HashSet<>(10);
        final ListOrderedSet<E> orderedSet = ListOrderedSet.listOrderedSet(set, list);
        for (int i = 0; i < 10; ++i) {
            orderedSet.add((E) Integer.valueOf(10 - i - 1));
        }

        final Collection<E> retained = new ArrayList<>(5);
        for (int i = 0; i < 5; ++i) {
            retained.add((E) Integer.valueOf(i * 2));
        }

        assertTrue(orderedSet.retainAll(retained));
        assertEquals(5, orderedSet.size());
        // insertion order preserved?
        assertEquals(Integer.valueOf(8), orderedSet.get(0));
        assertEquals(Integer.valueOf(6), orderedSet.get(1));
        assertEquals(Integer.valueOf(4), orderedSet.get(2));
        assertEquals(Integer.valueOf(2), orderedSet.get(3));
        assertEquals(Integer.valueOf(0), orderedSet.get(4));
    }

//    void testCreate() throws Exception {
//        resetEmpty();
//        writeExternalFormToDisk((java.io.Serializable) getCollection(), "src/test/resources/data/test/ListOrderedSet.emptyCollection.version4.obj");
//        resetFull();
//        writeExternalFormToDisk((java.io.Serializable) getCollection(), "src/test/resources/data/test/ListOrderedSet.fullCollection.version4.obj");
//    }

}