/*
* Written by Doug Lea with assistance from members of JCP JSR-166
* Expert Group and released to the public domain, as explained at
* http://creativecommons.org/publicdomain/zero/1.0/
* Other contributors include Andrew Wright, Jeffrey Hayes,
* Pat Fisher, Mike Judd.
*/
package jsr166;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Iterator;
import java.util.Map;
import java.util.Random;
import java.util.Set;
import java.util.concurrent.ConcurrentMap;
import com.github.benmanes.caffeine.cache.Caffeine;
import junit.framework.Test;
import junit.framework.TestSuite;
@SuppressWarnings({"rawtypes", "unchecked"})
public class ConcurrentHashMapTest extends JSR166TestCase {
public static void main(String[] args) {
junit.textui.TestRunner.run(suite());
}
public static Test suite() {
return new TestSuite(ConcurrentHashMapTest.class);
}
private static <K, V> ConcurrentMap<K, V> map() {
return Caffeine.newBuilder()
.maximumSize(Integer.MAX_VALUE)
.<K, V>build().asMap();
}
/**
* Returns a new map from Integers 1-5 to Strings "A"-"E".
*/
private static ConcurrentMap<Integer, String> map5() {
ConcurrentMap map = map();
assertTrue(map.isEmpty());
map.put(one, "A");
map.put(two, "B");
map.put(three, "C");
map.put(four, "D");
map.put(five, "E");
assertFalse(map.isEmpty());
assertEquals(5, map.size());
return map;
}
/** Re-implement Integer.compare for old java versions */
static int compare(int x, int y) { return x < y ? -1 : x > y ? 1 : 0; }
// classes for testing Comparable fallbacks
static class BI implements Comparable<BI> {
private final int value;
BI(int value) { this.value = value; }
@Override
public int compareTo(BI other) {
return compare(value, other.value);
}
@Override
public boolean equals(Object x) {
return (x instanceof BI) && ((BI)x).value == value;
}
@Override
public int hashCode() { return 42; }
}
static class CI extends BI { CI(int value) { super(value); } }
static class DI extends BI { DI(int value) { super(value); } }
static class BS implements Comparable<BS> {
private final String value;
BS(String value) { this.value = value; }
@Override
public int compareTo(BS other) {
return value.compareTo(other.value);
}
@Override
public boolean equals(Object x) {
return (x instanceof BS) && value.equals(((BS)x).value);
}
@Override
public int hashCode() { return 42; }
}
static class LexicographicList<E extends Comparable<E>> extends ArrayList<E>
implements Comparable<LexicographicList<E>> {
LexicographicList(Collection<E> c) { super(c); }
LexicographicList(E e) { super(Collections.singleton(e)); }
@Override
public int compareTo(LexicographicList<E> other) {
int common = Math.min(size(), other.size());
int r = 0;
for (int i = 0; i < common; i++) {
if ((r = get(i).compareTo(other.get(i))) != 0) {
break;
}
}
if (r == 0) {
r = compare(size(), other.size());
}
return r;
}
private static final long serialVersionUID = 0;
}
static class CollidingObject {
final String value;
CollidingObject(final String value) { this.value = value; }
@Override
public int hashCode() { return this.value.hashCode() & 1; }
@Override
public boolean equals(final Object obj) {
return (obj instanceof CollidingObject) && ((CollidingObject)obj).value.equals(value);
}
}
static class ComparableCollidingObject extends CollidingObject implements Comparable<ComparableCollidingObject> {
ComparableCollidingObject(final String value) { super(value); }
@Override
public int compareTo(final ComparableCollidingObject o) {
return value.compareTo(o.value);
}
}
/**
* Inserted elements that are subclasses of the same Comparable
* class are found.
*/
public void testComparableFamily() {
int size = 500; // makes measured test run time -> 60ms
ConcurrentMap<BI, Boolean> m = map();
for (int i = 0; i < size; i++) {
assertTrue(m.put(new CI(i), true) == null);
}
for (int i = 0; i < size; i++) {
assertTrue(m.containsKey(new CI(i)));
assertTrue(m.containsKey(new DI(i)));
}
}
/**
* Elements of classes with erased generic type parameters based
* on Comparable can be inserted and found.
*/
public void testGenericComparable() {
int size = 120; // makes measured test run time -> 60ms
ConcurrentMap<Object, Boolean> m = map();
for (int i = 0; i < size; i++) {
BI bi = new BI(i);
BS bs = new BS(String.valueOf(i));
LexicographicList<BI> bis = new LexicographicList<BI>(bi);
LexicographicList<BS> bss = new LexicographicList<BS>(bs);
assertTrue(m.putIfAbsent(bis, true) == null);
assertTrue(m.containsKey(bis));
if (m.putIfAbsent(bss, true) == null) {
assertTrue(m.containsKey(bss));
}
assertTrue(m.containsKey(bis));
}
for (int i = 0; i < size; i++) {
assertTrue(m.containsKey(Collections.singletonList(new BI(i))));
}
}
/**
* Elements of non-comparable classes equal to those of classes
* with erased generic type parameters based on Comparable can be
* inserted and found.
*/
public void testGenericComparable2() {
int size = 500; // makes measured test run time -> 60ms
ConcurrentMap<Object, Boolean> m = map();
for (int i = 0; i < size; i++) {
m.put(Collections.singletonList(new BI(i)), true);
}
for (int i = 0; i < size; i++) {
LexicographicList<BI> bis = new LexicographicList<BI>(new BI(i));
assertTrue(m.containsKey(bis));
}
}
/**
* Mixtures of instances of comparable and non-comparable classes
* can be inserted and found.
*/
public void testMixedComparable() {
int size = 1200; // makes measured test run time -> 35ms
ConcurrentMap<Object, Object> map = map();
Random rng = new Random();
for (int i = 0; i < size; i++) {
Object x;
switch (rng.nextInt(4)) {
case 0:
x = new Object();
break;
case 1:
x = new CollidingObject(Integer.toString(i));
break;
default:
x = new ComparableCollidingObject(Integer.toString(i));
}
assertNull(map.put(x, x));
}
int count = 0;
for (Object k : map.keySet()) {
assertEquals(map.get(k), k);
++count;
}
assertEquals(count, size);
assertEquals(map.size(), size);
for (Object k : map.keySet()) {
assertEquals(map.put(k, k), k);
}
}
/**
* clear removes all pairs
*/
public void testClear() {
ConcurrentMap map = map5();
map.clear();
assertEquals(0, map.size());
}
/**
* Maps with same contents are equal
*/
public void testEquals() {
ConcurrentMap map1 = map5();
ConcurrentMap map2 = map5();
assertEquals(map1, map2);
assertEquals(map2, map1);
map1.clear();
assertFalse(map1.equals(map2));
assertFalse(map2.equals(map1));
}
/**
* hashCode() equals sum of each key.hashCode ^ value.hashCode
*/
public void testHashCode() {
ConcurrentMap<Integer,String> map = map5();
int sum = 0;
for (Map.Entry<Integer,String> e : map.entrySet()) {
sum += e.getKey().hashCode() ^ e.getValue().hashCode();
}
assertEquals(sum, map.hashCode());
}
/**
* containsKey returns true for contained key
*/
public void testContainsKey() {
ConcurrentMap map = map5();
assertTrue(map.containsKey(one));
assertFalse(map.containsKey(zero));
}
/**
* containsValue returns true for held values
*/
public void testContainsValue() {
ConcurrentMap map = map5();
assertTrue(map.containsValue("A"));
assertFalse(map.containsValue("Z"));
}
/**
* get returns the correct element at the given key,
* or null if not present
*/
public void testGet() {
ConcurrentMap map = map5();
assertEquals("A", (String)map.get(one));
ConcurrentMap empty = map();
assertNull(map.get("anything"));
assertNull(empty.get("anything"));
}
/**
* isEmpty is true of empty map and false for non-empty
*/
public void testIsEmpty() {
ConcurrentMap empty = map();
ConcurrentMap map = map5();
assertTrue(empty.isEmpty());
assertFalse(map.isEmpty());
}
/**
* keySet returns a Set containing all the keys
*/
public void testKeySet() {
ConcurrentMap map = map5();
Set s = map.keySet();
assertEquals(5, s.size());
assertTrue(s.contains(one));
assertTrue(s.contains(two));
assertTrue(s.contains(three));
assertTrue(s.contains(four));
assertTrue(s.contains(five));
}
/**
* keySet.toArray returns contains all keys
*/
public void testKeySetToArray() {
ConcurrentMap map = map5();
Set s = map.keySet();
Object[] ar = s.toArray();
assertTrue(s.containsAll(Arrays.asList(ar)));
assertEquals(5, ar.length);
ar[0] = m10;
assertFalse(s.containsAll(Arrays.asList(ar)));
}
/**
* Values.toArray contains all values
*/
public void testValuesToArray() {
ConcurrentMap map = map5();
Collection v = map.values();
Object[] ar = v.toArray();
ArrayList s = new ArrayList(Arrays.asList(ar));
assertEquals(5, ar.length);
assertTrue(s.contains("A"));
assertTrue(s.contains("B"));
assertTrue(s.contains("C"));
assertTrue(s.contains("D"));
assertTrue(s.contains("E"));
}
/**
* entrySet.toArray contains all entries
*/
public void testEntrySetToArray() {
ConcurrentMap map = map5();
Set s = map.entrySet();
Object[] ar = s.toArray();
assertEquals(5, ar.length);
for (int i = 0; i < 5; ++i) {
assertTrue(map.containsKey(((Map.Entry)(ar[i])).getKey()));
assertTrue(map.containsValue(((Map.Entry)(ar[i])).getValue()));
}
}
/**
* values collection contains all values
*/
public void testValues() {
ConcurrentMap map = map5();
Collection s = map.values();
assertEquals(5, s.size());
assertTrue(s.contains("A"));
assertTrue(s.contains("B"));
assertTrue(s.contains("C"));
assertTrue(s.contains("D"));
assertTrue(s.contains("E"));
}
/**
* entrySet contains all pairs
*/
public void testEntrySet() {
ConcurrentMap map = map5();
Set s = map.entrySet();
assertEquals(5, s.size());
Iterator it = s.iterator();
while (it.hasNext()) {
Map.Entry e = (Map.Entry) it.next();
assertTrue(
(e.getKey().equals(one) && e.getValue().equals("A")) ||
(e.getKey().equals(two) && e.getValue().equals("B")) ||
(e.getKey().equals(three) && e.getValue().equals("C")) ||
(e.getKey().equals(four) && e.getValue().equals("D")) ||
(e.getKey().equals(five) && e.getValue().equals("E")));
}
}
/**
* putAll adds all key-value pairs from the given map
*/
public void testPutAll() {
ConcurrentMap empty = map();
ConcurrentMap map = map5();
empty.putAll(map);
assertEquals(5, empty.size());
assertTrue(empty.containsKey(one));
assertTrue(empty.containsKey(two));
assertTrue(empty.containsKey(three));
assertTrue(empty.containsKey(four));
assertTrue(empty.containsKey(five));
}
/**
* putIfAbsent works when the given key is not present
*/
public void testPutIfAbsent() {
ConcurrentMap map = map5();
map.putIfAbsent(six, "Z");
assertTrue(map.containsKey(six));
}
/**
* putIfAbsent does not add the pair if the key is already present
*/
public void testPutIfAbsent2() {
ConcurrentMap map = map5();
assertEquals("A", map.putIfAbsent(one, "Z"));
}
/**
* replace fails when the given key is not present
*/
public void testReplace() {
ConcurrentMap map = map5();
assertNull(map.replace(six, "Z"));
assertFalse(map.containsKey(six));
}
/**
* replace succeeds if the key is already present
*/
public void testReplace2() {
ConcurrentMap map = map5();
assertNotNull(map.replace(one, "Z"));
assertEquals("Z", map.get(one));
}
/**
* replace value fails when the given key not mapped to expected value
*/
public void testReplaceValue() {
ConcurrentMap map = map5();
assertEquals("A", map.get(one));
assertFalse(map.replace(one, "Z", "Z"));
assertEquals("A", map.get(one));
}
/**
* replace value succeeds when the given key mapped to expected value
*/
public void testReplaceValue2() {
ConcurrentMap map = map5();
assertEquals("A", map.get(one));
assertTrue(map.replace(one, "A", "Z"));
assertEquals("Z", map.get(one));
}
/**
* remove removes the correct key-value pair from the map
*/
public void testRemove() {
ConcurrentMap map = map5();
map.remove(five);
assertEquals(4, map.size());
assertFalse(map.containsKey(five));
}
/**
* remove(key,value) removes only if pair present
*/
public void testRemove2() {
ConcurrentMap map = map5();
map.remove(five, "E");
assertEquals(4, map.size());
assertFalse(map.containsKey(five));
map.remove(four, "A");
assertEquals(4, map.size());
assertTrue(map.containsKey(four));
}
/**
* size returns the correct values
*/
public void testSize() {
ConcurrentMap map = map5();
ConcurrentMap empty = map();
assertEquals(0, empty.size());
assertEquals(5, map.size());
}
/**
* toString contains toString of elements
*/
public void testToString() {
ConcurrentMap map = map5();
String s = map.toString();
for (int i = 1; i <= 5; ++i) {
assertTrue(s.contains(String.valueOf(i)));
}
}
// Exception tests
/**
* get(null) throws NPE
*/
public void testGet_NullPointerException() {
ConcurrentMap c = map();
try {
c.get(null);
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* containsKey(null) throws NPE
*/
public void testContainsKey_NullPointerException() {
ConcurrentMap c = map();
try {
c.containsKey(null);
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* containsValue(null) throws NPE
*/
public void testContainsValue_NullPointerException() {
ConcurrentMap c = map();
try {
c.containsValue(null);
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* put(null,x) throws NPE
*/
public void testPut1_NullPointerException() {
ConcurrentMap c = map();
try {
c.put(null, "whatever");
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* put(x, null) throws NPE
*/
public void testPut2_NullPointerException() {
ConcurrentMap c = map();
try {
c.put("whatever", null);
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* putIfAbsent(null, x) throws NPE
*/
public void testPutIfAbsent1_NullPointerException() {
ConcurrentMap c = map();
try {
c.putIfAbsent(null, "whatever");
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* replace(null, x) throws NPE
*/
public void testReplace_NullPointerException() {
ConcurrentMap c = map();
try {
c.replace(null, "whatever");
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* replace(null, x, y) throws NPE
*/
public void testReplaceValue_NullPointerException() {
ConcurrentMap c = map();
try {
c.replace(null, one, "whatever");
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* putIfAbsent(x, null) throws NPE
*/
public void testPutIfAbsent2_NullPointerException() {
ConcurrentMap c = map();
try {
c.putIfAbsent("whatever", null);
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* replace(x, null) throws NPE
*/
public void testReplace2_NullPointerException() {
ConcurrentMap c = map();
try {
c.replace("whatever", null);
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* replace(x, null, y) throws NPE
*/
public void testReplaceValue2_NullPointerException() {
ConcurrentMap c = map();
try {
c.replace("whatever", null, "A");
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* replace(x, y, null) throws NPE
*/
public void testReplaceValue3_NullPointerException() {
ConcurrentMap c = map();
try {
c.replace("whatever", one, null);
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* remove(null) throws NPE
*/
public void testRemove1_NullPointerException() {
ConcurrentMap c = map();
c.put("sadsdf", "asdads");
try {
c.remove(null);
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* remove(null, x) throws NPE
*/
public void testRemove2_NullPointerException() {
ConcurrentMap c = map();
c.put("sadsdf", "asdads");
try {
c.remove(null, "whatever");
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* remove(x, null) returns false
*/
public void testRemove3() {
ConcurrentMap c = map();
c.put("sadsdf", "asdads");
assertFalse(c.remove("sadsdf", null));
}
/**
* SetValue of an EntrySet entry sets value in the map.
*/
public void testSetValueWriteThrough() {
// Adapted from a bug report by Eric Zoerner
ConcurrentMap map = map();
assertTrue(map.isEmpty());
for (int i = 0; i < 20; i++) {
map.put(i, i);
}
assertFalse(map.isEmpty());
Map.Entry entry1 = (Map.Entry)map.entrySet().iterator().next();
// Unless it happens to be first (in which case remainder of
// test is skipped), remove a possibly-colliding key from map
// which, under some implementations, may cause entry1 to be
// cloned in map
if (!entry1.getKey().equals(16)) {
map.remove(16);
entry1.setValue("XYZ");
assertTrue(map.containsValue("XYZ")); // fails if write-through broken
}
}
}