/*
* Copyright 2000-2009 JetBrains s.r.o.
*
* 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.intellij.util.containers.hash;
import org.junit.Assert;
import org.junit.Test;
import java.util.Iterator;
import java.util.Map;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertNull;
public class LinkedHashMapTest {
@Test
public void testPutGet() {
final LinkedHashMap<Integer, String> tested = new LinkedHashMap<>();
for (int i = 0; i < 1000; ++i) {
tested.put(i, Integer.toString(i));
}
assertEquals(1000, tested.size());
for (int i = 0; i < 1000; ++i) {
assertEquals(Integer.toString(i), tested.get(i));
}
for (int i = 0; i < 1000; ++i) {
assertEquals(Integer.toString(i), tested.put(i, Integer.toString(i + 1)));
}
assertEquals(1000, tested.size());
for (int i = 0; i < 1000; ++i) {
assertEquals(Integer.toString(i + 1), tested.get(i));
}
}
@Test
public void testPutGet2() {
final LinkedHashMap<Integer, String> tested = new LinkedHashMap<>();
for (int i = 0; i < 1000; ++i) {
tested.put(i - 500, Integer.toString(i));
}
assertEquals(1000, tested.size());
for (int i = 0; i < 1000; ++i) {
assertEquals(Integer.toString(i), tested.get(i - 500));
}
for (int i = 0; i < 1000; ++i) {
assertEquals(Integer.toString(i), tested.put(i - 500, Integer.toString(i + 1)));
}
assertEquals(1000, tested.size());
for (int i = 0; i < 1000; ++i) {
assertEquals(Integer.toString(i + 1), tested.get(i - 500));
}
}
@Test
public void testPutGetRemove() {
final LinkedHashMap<Integer, String> tested = new LinkedHashMap<>();
for (int i = 0; i < 1000; ++i) {
tested.put(i, Integer.toString(i));
}
assertEquals(1000, tested.size());
for (int i = 0; i < 1000; i += 2) {
assertEquals(Integer.toString(i), tested.remove(i));
}
assertEquals(500, tested.size());
for (int i = 0; i < 1000; ++i) {
assertEquals((i % 2 == 0) ? null : Integer.toString(i), tested.get(i));
}
}
@Test
public void keySet() {
final LinkedHashMap<Integer, String> tested = new LinkedHashMap<>();
for (int i = 0; i < 10000; ++i) {
tested.put(i, Integer.toString(i));
}
int i = 0;
for (Integer key : tested.keySet()) {
assertEquals(i++, key.intValue());
}
}
@Test
public void keySet2() {
final LinkedHashMap<Integer, String> tested = new LinkedHashMap<>();
for (int i = 0; i < 10000; ++i) {
tested.put(i, Integer.toString(i));
}
Iterator<Integer> it = tested.keySet().iterator();
while (it.hasNext()) {
final int i = it.next();
if (i % 2 == 0) {
it.remove();
}
}
assertEquals(5000, tested.size());
it = tested.keySet().iterator();
for (int i = 1; i <= 9999; i += 2) {
Assert.assertTrue(it.hasNext());
assertEquals(i, it.next().intValue());
}
}
@Test
public void lru() {
final LinkedHashMap<Integer, String> tested = new LinkedHashMap<Integer, String>() {
@Override
protected boolean removeEldestEntry(Map.Entry<Integer, String> eldest) {
return size() > 500;
}
};
for (int i = 0; i < 1000; ++i) {
tested.put(i, Integer.toString(i));
}
assertEquals(500, tested.size());
for (int i = 0; i < 500; ++i) {
Assert.assertNull(tested.remove(i));
}
assertEquals(500, tested.size());
for (int i = 500; i < 1000; ++i) {
assertEquals(Integer.toString(i), tested.remove(i));
}
assertEquals(0, tested.size());
}
@Test
public void lru2() {
final LinkedHashMap<Integer, String> tested = new LinkedHashMap<Integer, String>(0, true) {
@Override
protected boolean removeEldestEntry(Map.Entry<Integer, String> eldest) {
return size() > 1000;
}
};
for (int i = 0; i < 1000; ++i) {
tested.put(i, Integer.toString(i));
}
assertEquals(Integer.toString(0), tested.get(0));
for (int i = 1000; i < 1999; ++i) {
tested.put(i, Integer.toString(i));
}
assertEquals(Integer.toString(0), tested.get(0));
tested.put(2000, Integer.toString(2000));
Assert.assertNull(tested.get(1000));
}
@Test
public void lru3() {
final LinkedHashMap<Integer, String> tested = new LinkedHashMap<Integer, String>(0, true) {
@Override
protected boolean removeEldestEntry(Map.Entry<Integer, String> eldest) {
return size() > 1000;
}
};
for (int i = 0; i < 1000; ++i) {
tested.put(i, Integer.toString(i));
}
assertEquals(Integer.toString(999), tested.remove(999));
assertEquals(999, tested.size());
assertEquals(Integer.toString(0), tested.get(0));
for (int i = 1000; i < 1999; ++i) {
tested.put(i, Integer.toString(i));
}
assertEquals(Integer.toString(0), tested.get(0));
tested.put(2000, Integer.toString(2000));
assertNull(tested.get(1000));
}
@Test
public void valuesIteration() {
Map<Integer, String> map = new LinkedHashMap<>();
map.put(1, "a");
map.put(2, "b");
map.put(3, "c");
Iterator<String> iterator = map.values().iterator();
assertEquals("a", iterator.next());
assertEquals("b", iterator.next());
assertEquals("c", iterator.next());
assertFalse(iterator.hasNext());
}
@Test
public void accessOrderValuesIteration() {
Map<Integer, String> map = new LinkedHashMap<>(0, true);
map.put(1, "a");
map.put(2, "b");
map.put(3, "c");
Iterator<String> iterator = map.values().iterator();
assertEquals("a", iterator.next());
assertEquals("b", iterator.next());
assertEquals("c", iterator.next());
assertFalse(iterator.hasNext());
}
@Test
public void lastAddedKey() {
LinkedHashMap<Integer, String> map = new LinkedHashMap<>();
map.put(1, "a");
map.put(2, "b");
map.put(3, "c");
map.get(1);
map.get(2);
assertEquals(3, map.getLastKey().intValue());
assertEquals("c", map.getLastValue());
map.remove(2);
assertEquals(3, map.getLastKey().intValue());
assertEquals("c", map.getLastValue());
map.remove(3);
assertEquals(1, map.getLastKey().intValue());
assertEquals("a", map.getLastValue());
map.remove(1);
assertNull(map.getLastKey());
assertNull(map.getLastValue());
}
//@Test
public void benchmarkGet() {
long started;
final Map<Integer, String> map = new java.util.LinkedHashMap<>();
for (int i = 0; i < 100000; ++i) {
map.put(i, Integer.toString(i));
}
started = System.currentTimeMillis();
for (int i = 0; i < 1000; ++i) {
for (int j = 0; j < 100000; ++j) {
map.get(j);
}
}
System.out.println("100 000 000 lookups in java.util.LinkedHashMap took " + (System.currentTimeMillis() - started));
final LinkedHashMap<Integer, String> tested = new LinkedHashMap<>();
for (int i = 0; i < 100000; ++i) {
tested.put(i, Integer.toString(i));
}
started = System.currentTimeMillis();
for (int i = 0; i < 1000; ++i) {
for (int j = 0; j < 100000; ++j) {
tested.get(j);
}
}
System.out.println("100 000 000 lookups in LinkedHashMap took " + (System.currentTimeMillis() - started));
}
//@Test
public void benchmarkGetMissingKeys() {
long started;
final Map<Integer, String> map = new java.util.LinkedHashMap<>();
for (int i = 0; i < 100000; ++i) {
map.put(i, Integer.toString(i));
}
started = System.currentTimeMillis();
for (int i = 0; i < 1000; ++i) {
for (int j = 0; j < 100000; ++j) {
map.get(j + 1000000);
}
}
System.out.println("100 000 000 lookups in java.util.LinkedHashMap took " + (System.currentTimeMillis() - started));
final LinkedHashMap<Integer, String> tested = new LinkedHashMap<>();
for (int i = 0; i < 100000; ++i) {
tested.put(i, Integer.toString(i));
}
started = System.currentTimeMillis();
for (int i = 0; i < 1000; ++i) {
for (int j = 0; j < 100000; ++j) {
tested.get(j + 1000000);
}
}
System.out.println("100 000 000 lookups in LinkedHashMap took " + (System.currentTimeMillis() - started));
}
//@Test
public void benchmarkLRU() {
long started;
final Map<Integer, String> map = new java.util.LinkedHashMap<>();
for (int i = 0; i < 100000; ++i) {
map.put(i, Integer.toString(i));
}
started = System.currentTimeMillis();
for (int i = 0; i < 200; ++i) {
for (int j = 0; j < 100000; ++j) {
final String v = map.remove(j);
map.put(j, v);
}
}
System.out.println("20 000 000 LRU lookups in java.util.LinkedHashMap took " + (System.currentTimeMillis() - started));
final LinkedHashMap<Integer, String> tested = new LinkedHashMap<>();
for (int i = 0; i < 100000; ++i) {
tested.put(i, Integer.toString(i));
}
started = System.currentTimeMillis();
for (int i = 0; i < 200; ++i) {
for (int j = 0; j < 100000; ++j) {
tested.get(j);
}
}
System.out.println("20 000 000 lookups in LinkedHashMap took " + (System.currentTimeMillis() - started));
}
}