/*
* Copyright Terracotta, Inc.
*
* 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 org.ehcache.impl.internal.concurrent;
import org.junit.Test;
import java.util.Comparator;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Random;
import org.ehcache.config.Eviction;
import org.ehcache.config.EvictionAdvisor;
import static org.ehcache.config.Eviction.noAdvice;
import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.core.IsNull.notNullValue;
import static org.hamcrest.core.IsNull.nullValue;
import static org.hamcrest.number.OrderingComparison.greaterThan;
import static org.junit.Assert.assertThat;
/**
* @author Alex Snaps
*/
public class ConcurrentHashMapTest {
@Test
public void testRemoveAllWithHash() throws Exception {
final int totalCount = 10037;
ConcurrentHashMap<Comparable<?>, String> map = new ConcurrentHashMap<Comparable<?>, String>();
int lastHash = 0;
for(int i = 0; i < totalCount; i++) {
String o = Integer.toString(i);
lastHash = o.hashCode();
map.put(o, "val#" + i);
}
Map<Comparable<?>, String> removed = map.removeAllWithHash(lastHash);
assertThat(removed.size(), greaterThan(0));
assertThat(map.size() + removed.size(), is(totalCount));
for (Comparable<?> key : map.keySet()) {
assertThat(removed.containsKey(key), is(false));
}
}
@Test
public void testRemoveAllWithHashUsingBadHashes() throws Exception {
final int totalCount = 10037;
ConcurrentHashMap<Comparable<?>, String> map = new ConcurrentHashMap<Comparable<?>, String>();
for(int i = 0; i < totalCount; i++) {
BadHashKey o = new BadHashKey(i);
map.put(o, "val#" + i);
}
Map<Comparable<?>, String> removed = map.removeAllWithHash(BadHashKey.HASH_CODE);
assertThat(removed.size(), is(totalCount));
assertThat(map.size(), is(0));
for (Comparable<?> removedKey : removed.keySet()) {
assertThat(map.containsKey(removedKey), is(false));
}
}
static class BadHashKey implements Comparable<BadHashKey> {
static final int HASH_CODE = 42;
private final int value;
public BadHashKey(int value) {
this.value = value;
}
@Override
public String toString() {
return "BadHashKey#" + value;
}
@Override
public boolean equals(Object obj) {
if (obj instanceof BadHashKey) {
return ((BadHashKey) obj).value == value;
}
return false;
}
@Override
public int hashCode() {
return HASH_CODE;
}
@Override
public int compareTo(BadHashKey o) {
return (value < o.value) ? -1 : ((value > o.value) ? 1 : 0);
}
}
@Test
public void testRandomSampleOnEmptyMap() {
ConcurrentHashMap<String, String> map = new ConcurrentHashMap<String, String>();
assertThat(map.getEvictionCandidate(new Random(), 1, null, noAdvice()), nullValue());
}
@Test
public void testEmptyRandomSample() {
ConcurrentHashMap<String, String> map = new ConcurrentHashMap<String, String>();
map.put("foo", "bar");
assertThat(map.getEvictionCandidate(new Random(), 0, null, noAdvice()), nullValue());
}
@Test
public void testOversizedRandomSample() {
ConcurrentHashMap<String, String> map = new ConcurrentHashMap<String, String>();
map.put("foo", "bar");
Entry<String, String> candidate = map.getEvictionCandidate(new Random(), 2, null, noAdvice());
assertThat(candidate.getKey(), is("foo"));
assertThat(candidate.getValue(), is("bar"));
}
@Test
public void testUndersizedRandomSample() {
ConcurrentHashMap<String, String> map = new ConcurrentHashMap<String, String>();
for (int i = 0; i < 1000; i++) {
map.put(Integer.toString(i), Integer.toString(i));
}
Entry<String, String> candidate = map.getEvictionCandidate(new Random(), 2, new Comparator<String>() {
@Override
public int compare(String t, String t1) {
return 0;
}
}, noAdvice());
assertThat(candidate, notNullValue());
}
@Test
public void testFullyAdvisedAgainstEvictionRandomSample() {
ConcurrentHashMap<String, String> map = new ConcurrentHashMap<String, String>();
for (int i = 0; i < 1000; i++) {
map.put(Integer.toString(i), Integer.toString(i));
}
Entry<String, String> candidate = map.getEvictionCandidate(new Random(), 2, null, new EvictionAdvisor<String, String>() {
@Override
public boolean adviseAgainstEviction(String key, String value) {
return true;
}
});
assertThat(candidate, nullValue());
}
@Test
public void testSelectivelyAdvisedAgainstEvictionRandomSample() {
ConcurrentHashMap<String, String> map = new ConcurrentHashMap<String, String>();
for (int i = 0; i < 1000; i++) {
map.put(Integer.toString(i), Integer.toString(i));
}
Entry<String, String> candidate = map.getEvictionCandidate(new Random(), 20, new Comparator<String>() {
@Override
public int compare(String t, String t1) {
return 0;
}
}, new EvictionAdvisor<String, String>() {
@Override
public boolean adviseAgainstEviction(String key, String value) {
return key.length() > 1;
}
});
assertThat(candidate.getKey().length(), is(1));
}
@Test
public void testReplaceWithWeirdBehavior() {
ConcurrentHashMap<String, Element> elementMap = new ConcurrentHashMap<String, Element>();
final Element initialElement = new Element("key", "foo");
elementMap.put("key", initialElement);
assertThat(elementMap.replace("key", initialElement, new Element("key", "foo")), is(true));
assertThat(elementMap.replace("key", initialElement, new Element("key", "foo")), is(false));
ConcurrentHashMap<String, String> stringMap = new ConcurrentHashMap<String, String>();
final String initialString = "foo";
stringMap.put("key", initialString);
assertThat(stringMap.replace("key", initialString, new String(initialString)), is(true));
assertThat(stringMap.replace("key", initialString, new String(initialString)), is(true));
}
@Test
public void testUsesObjectIdentityForElementsOnly() {
final String key = "ourKey";
ConcurrentHashMap<String, Object> map = new ConcurrentHashMap<String, Object>();
String value = new String("key");
String valueAgain = new String("key");
map.put(key, value);
assertThat(map.replace(key, valueAgain, valueAgain), is(true));
assertThat(map.replace(key, value, valueAgain), is(true));
Element elementValue = new Element(key, value);
Element elementValueAgain = new Element(key, value);
map.put(key, elementValue);
assertThat(map.replace(key, elementValueAgain, elementValue), is(false));
assertThat(map.replace(key, elementValue, elementValueAgain), is(true));
assertThat(map.replace(key, elementValue, elementValueAgain), is(false));
assertThat(map.replace(key, elementValueAgain, elementValue), is(true));
}
static class Element {
@SuppressWarnings("unused")
private final Object key;
@SuppressWarnings("unused")
private final Object value;
Element(final Object key, final Object value) {
this.key = key;
this.value = value;
}
}
}