CombinationTest.java example

Explorer
speedment-master
/**
 *
 * Copyright (c) 2006-2017, Speedment, Inc. All Rights Reserved.
 *
 * 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 com.speedment.common.combinatorics;

import java.util.Arrays;
import java.util.List;
import java.util.Set;
import static java.util.stream.Collectors.toList;
import static java.util.stream.Collectors.toSet;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;
import org.junit.Test;

/**
 *
 * @author Per Minborg
 */
public class CombinationTest {

    @Test
    public void testOfEmpty() {
        final List<List<String>> actual = Combination.<String>of()
            .collect(toList());
        assertTrue(actual.isEmpty());
    }

    @Test
    public void testOfSingleton() {
        final List<List<String>> actual = Combination.of("a")
            .collect(toList());

        assertEquals(
            Arrays.asList(
                Arrays.asList("a")
            ),
            actual
        );
    }

    @Test
    public void testOfTwo() {
        final Set<List<String>> actual = Combination.of("a", "b")
            .collect(toSet());

        final Set<List<String>> expected = Arrays.asList(
            Arrays.asList("a"),
            Arrays.asList("a", "a"),
            Arrays.asList("a", "b"),
            Arrays.asList("b"),
            Arrays.asList("b", "b"),
            Arrays.asList("b", "a")
        ).stream().collect(toSet());

        assertEquals(expected, actual);

    }

    @Test
    public void testOfThree() {
        Set<List<String>> actual = Combination.of("a", "b", "c")
            .collect(toSet());

        final Set<List<String>> expected = Arrays.asList(
            Arrays.asList("a"),
            Arrays.asList("b"),
            Arrays.asList("c"),
            Arrays.asList("a", "a"),
            Arrays.asList("a", "b"),
            Arrays.asList("a", "c"),
            Arrays.asList("b", "a"),
            Arrays.asList("b", "b"),
            Arrays.asList("b", "c"),
            Arrays.asList("c", "a"),
            Arrays.asList("c", "b"),
            Arrays.asList("c", "c"),
            Arrays.asList("a", "a", "a"),
            Arrays.asList("a", "a", "b"),
            Arrays.asList("a", "a", "c"),
            Arrays.asList("a", "b", "a"),
            Arrays.asList("a", "b", "b"),
            Arrays.asList("a", "b", "c"),
            Arrays.asList("a", "c", "a"),
            Arrays.asList("a", "c", "b"),
            Arrays.asList("a", "c", "c"),
            Arrays.asList("b", "a", "a"),
            Arrays.asList("b", "a", "b"),
            Arrays.asList("b", "a", "c"),
            Arrays.asList("b", "b", "a"),
            Arrays.asList("b", "b", "b"),
            Arrays.asList("b", "b", "c"),
            Arrays.asList("b", "c", "a"),
            Arrays.asList("b", "c", "b"),
            Arrays.asList("b", "c", "c"),
            Arrays.asList("c", "a", "a"),
            Arrays.asList("c", "a", "b"),
            Arrays.asList("c", "a", "c"),
            Arrays.asList("c", "b", "a"),
            Arrays.asList("c", "b", "b"),
            Arrays.asList("c", "b", "c"),
            Arrays.asList("c", "c", "a"),
            Arrays.asList("c", "c", "b"),
            Arrays.asList("c", "c", "c")
        ).stream().collect(toSet());

        assertEquals(expected, actual);

    }

    @Test
    public void testOfUniqueEmpty() {
        final List<List<String>> actual = Combination.<String>of()
            .collect(toList());
        assertTrue(actual.isEmpty());
    }

    @Test
    public void testOfUniqueSingleton() {
        final List<List<String>> actual = Combination.ofDistinct("a")
            .collect(toList());

        assertEquals(
            Arrays.asList(
                Arrays.asList("a")
            ),
            actual
        );
    }

    @Test
    public void testUniqueOfTwo() {
        final Set<List<String>> actual = Combination.ofDistinct("a", "b")
            .collect(toSet());

        final Set<List<String>> expected = Arrays.asList(
            Arrays.asList("a"),
            Arrays.asList("a", "b"),
            Arrays.asList("b"),
            Arrays.asList("b", "a")
        ).stream().collect(toSet());

        assertEquals(expected, actual);

    }

    @Test
    public void testOfUniqueThree() {
        Set<List<String>> actual = Combination.ofDistinct("a", "b", "c")
            .collect(toSet());

        final Set<List<String>> expected = Arrays.asList(
            Arrays.asList("a"),
            Arrays.asList("b"),
            Arrays.asList("c"),
            Arrays.asList("a", "b"),
            Arrays.asList("a", "c"),
            Arrays.asList("b", "a"),
            Arrays.asList("b", "c"),
            Arrays.asList("c", "a"),
            Arrays.asList("c", "b"),
            Arrays.asList("a", "b", "c"),
            Arrays.asList("a", "c", "b"),
            Arrays.asList("b", "a", "c"),
            Arrays.asList("b", "c", "a"),
            Arrays.asList("c", "a", "b"),
            Arrays.asList("c", "b", "a")
        ).stream().collect(toSet());

        assertEquals(expected, actual);
    }

}