/**
* 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
*
* 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.mahout.cf.taste.impl.common;
import com.google.common.collect.Maps;
import org.apache.mahout.cf.taste.impl.TasteTestCase;
import org.apache.mahout.common.RandomUtils;
import org.junit.Test;
import java.util.Map;
import java.util.Random;
/** <p>Tests {@link FastByIDMap}.</p> */
public final class FastByIDMapTest extends TasteTestCase {
@Test
public void testPutAndGet() {
FastByIDMap<Long> map = new FastByIDMap<Long>();
assertNull(map.get(500000L));
map.put(500000L, 2L);
assertEquals(2L, (long) map.get(500000L));
}
@Test
public void testRemove() {
FastByIDMap<Long> map = new FastByIDMap<Long>();
map.put(500000L, 2L);
map.remove(500000L);
assertEquals(0, map.size());
assertTrue(map.isEmpty());
assertNull(map.get(500000L));
}
@Test
public void testClear() {
FastByIDMap<Long> map = new FastByIDMap<Long>();
map.put(500000L, 2L);
map.clear();
assertEquals(0, map.size());
assertTrue(map.isEmpty());
assertNull(map.get(500000L));
}
@Test
public void testSizeEmpty() {
FastByIDMap<Long> map = new FastByIDMap<Long>();
assertEquals(0, map.size());
assertTrue(map.isEmpty());
map.put(500000L, 2L);
assertEquals(1, map.size());
assertFalse(map.isEmpty());
map.remove(500000L);
assertEquals(0, map.size());
assertTrue(map.isEmpty());
}
@Test
public void testContains() {
FastByIDMap<String> map = buildTestFastMap();
assertTrue(map.containsKey(500000L));
assertTrue(map.containsKey(47L));
assertTrue(map.containsKey(2L));
assertTrue(map.containsValue("alpha"));
assertTrue(map.containsValue("bang"));
assertTrue(map.containsValue("beta"));
assertFalse(map.containsKey(999));
assertFalse(map.containsValue("something"));
}
@Test
public void testRehash() {
FastByIDMap<String> map = buildTestFastMap();
map.remove(500000L);
map.rehash();
assertNull(map.get(500000L));
assertEquals("bang", map.get(47L));
}
@Test
public void testGrow() {
FastByIDMap<String> map = new FastByIDMap<String>(1,1);
map.put(500000L, "alpha");
map.put(47L, "bang");
assertNull(map.get(500000L));
assertEquals("bang", map.get(47L));
}
@Test
public void testVersusHashMap() {
FastByIDMap<String> actual = new FastByIDMap<String>();
Map<Long, String> expected = Maps.newHashMapWithExpectedSize(1000000);
Random r = RandomUtils.getRandom();
for (int i = 0; i < 1000000; i++) {
double d = r.nextDouble();
Long key = (long) r.nextInt(100);
if (d < 0.4) {
assertEquals(expected.get(key), actual.get(key));
} else {
if (d < 0.7) {
assertEquals(expected.put(key, "bang"), actual.put(key, "bang"));
} else {
assertEquals(expected.remove(key), actual.remove(key));
}
assertEquals(expected.size(), actual.size());
assertEquals(expected.isEmpty(), actual.isEmpty());
}
}
}
@Test
public void testMaxSize() {
FastByIDMap<String> map = new FastByIDMap<String>();
map.put(4, "bang");
assertEquals(1, map.size());
map.put(47L, "bang");
assertEquals(2, map.size());
assertNull(map.get(500000L));
map.put(47L, "buzz");
assertEquals(2, map.size());
assertEquals("buzz", map.get(47L));
}
private static FastByIDMap<String> buildTestFastMap() {
FastByIDMap<String> map = new FastByIDMap<String>();
map.put(500000L, "alpha");
map.put(47L, "bang");
map.put(2L, "beta");
return map;
}
}