SimpleFastItemIndexTest.java

/*
 * Copyright (C) 2016 RankSys http://ranksys.org
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 */
package es.uam.eps.ir.ranksys.fast.index;

import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Random;
import static java.util.stream.Collectors.toList;
import static java.util.stream.Collectors.toSet;
import java.util.stream.IntStream;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue;
import org.junit.Test;

/**
 * Unit test for SimpleFastItemIndex
 *
 * @author Saúl Vargas (Saul@VargasSandoval.es)
 */
public class SimpleFastItemIndexTest {

    /**
     * Tests main functionalities of the class.
     */
    @Test
    public void test() {
        Random rnd = new Random();
        
        int N = rnd.nextInt(5000);
        List<String> items = IntStream.range(0, N).mapToObj(Integer::toString).collect(toList());
        Collections.shuffle(items, rnd);

        FastItemIndex<String> itemIndex = SimpleFastItemIndex.load(items.stream());

        assertEquals(itemIndex.numItems(), N);

        rnd.ints(1000, 0, N)
                .forEach(iidx -> assertTrue(itemIndex.iidx2item(iidx).equals(items.get(iidx))));

        rnd.ints(1000, 0, N).mapToObj(Integer::toString)
                .forEach(item -> assertTrue(itemIndex.item2iidx(item) == items.indexOf(item)));

        rnd.ints(1000, 0, N).mapToObj(Integer::toString)
                .forEach(item -> assertTrue(itemIndex.containsItem(item)));

        rnd.ints(1000, N, 2 * N).mapToObj(Integer::toString)
                .forEach(item -> assertFalse(itemIndex.containsItem(item)));

        assertEquals(itemIndex.getAllItems().collect(toSet()), new HashSet<>(items));
    }

}