| 1 |
/* |
| 2 |
* Written by Doug Lea and Martin Buchholz with assistance from |
| 3 |
* members of JCP JSR-166 Expert Group and released to the public |
| 4 |
* domain, as explained at |
| 5 |
* http://creativecommons.org/publicdomain/zero/1.0/ |
| 6 |
*/ |
| 7 |
|
| 8 |
import java.util.ArrayList; |
| 9 |
import java.util.Collection; |
| 10 |
import java.util.Deque; |
| 11 |
import java.util.NoSuchElementException; |
| 12 |
import java.util.Queue; |
| 13 |
import java.util.concurrent.ThreadLocalRandom; |
| 14 |
import java.util.concurrent.atomic.AtomicReference; |
| 15 |
import java.util.function.Consumer; |
| 16 |
import java.util.function.Predicate; |
| 17 |
|
| 18 |
import junit.framework.Test; |
| 19 |
|
| 20 |
/** |
| 21 |
* Contains tests applicable to all Collection implementations. |
| 22 |
*/ |
| 23 |
public class CollectionTest extends JSR166TestCase { |
| 24 |
final CollectionImplementation impl; |
| 25 |
|
| 26 |
/** Tests are parameterized by a Collection implementation. */ |
| 27 |
CollectionTest(CollectionImplementation impl, String methodName) { |
| 28 |
super(methodName); |
| 29 |
this.impl = impl; |
| 30 |
} |
| 31 |
|
| 32 |
public static Test testSuite(CollectionImplementation impl) { |
| 33 |
return newTestSuite |
| 34 |
(parameterizedTestSuite(CollectionTest.class, |
| 35 |
CollectionImplementation.class, |
| 36 |
impl), |
| 37 |
jdk8ParameterizedTestSuite(CollectionTest.class, |
| 38 |
CollectionImplementation.class, |
| 39 |
impl)); |
| 40 |
} |
| 41 |
|
| 42 |
/** Checks properties of empty collections. */ |
| 43 |
public void testEmptyMeansEmpty() { |
| 44 |
Collection c = impl.emptyCollection(); |
| 45 |
assertTrue(c.isEmpty()); |
| 46 |
assertEquals(0, c.size()); |
| 47 |
assertEquals("[]", c.toString()); |
| 48 |
{ |
| 49 |
Object[] a = c.toArray(); |
| 50 |
assertEquals(0, a.length); |
| 51 |
assertSame(Object[].class, a.getClass()); |
| 52 |
} |
| 53 |
{ |
| 54 |
Object[] a = new Object[0]; |
| 55 |
assertSame(a, c.toArray(a)); |
| 56 |
} |
| 57 |
{ |
| 58 |
Integer[] a = new Integer[0]; |
| 59 |
assertSame(a, c.toArray(a)); |
| 60 |
} |
| 61 |
{ |
| 62 |
Integer[] a = { 1, 2, 3}; |
| 63 |
assertSame(a, c.toArray(a)); |
| 64 |
assertNull(a[0]); |
| 65 |
assertSame(2, a[1]); |
| 66 |
assertSame(3, a[2]); |
| 67 |
} |
| 68 |
assertIteratorExhausted(c.iterator()); |
| 69 |
Consumer alwaysThrows = (e) -> { throw new AssertionError(); }; |
| 70 |
c.forEach(alwaysThrows); |
| 71 |
c.iterator().forEachRemaining(alwaysThrows); |
| 72 |
c.spliterator().forEachRemaining(alwaysThrows); |
| 73 |
assertFalse(c.spliterator().tryAdvance(alwaysThrows)); |
| 74 |
if (Queue.class.isAssignableFrom(impl.klazz())) { |
| 75 |
Queue q = (Queue) c; |
| 76 |
assertNull(q.peek()); |
| 77 |
assertNull(q.poll()); |
| 78 |
} |
| 79 |
if (Deque.class.isAssignableFrom(impl.klazz())) { |
| 80 |
Deque d = (Deque) c; |
| 81 |
assertNull(d.peekFirst()); |
| 82 |
assertNull(d.peekLast()); |
| 83 |
assertNull(d.pollFirst()); |
| 84 |
assertNull(d.pollLast()); |
| 85 |
assertIteratorExhausted(d.descendingIterator()); |
| 86 |
} |
| 87 |
} |
| 88 |
|
| 89 |
public void testNullPointerExceptions() { |
| 90 |
Collection c = impl.emptyCollection(); |
| 91 |
assertThrows( |
| 92 |
NullPointerException.class, |
| 93 |
() -> c.addAll(null), |
| 94 |
() -> c.containsAll(null), |
| 95 |
() -> c.retainAll(null), |
| 96 |
() -> c.removeAll(null), |
| 97 |
() -> c.removeIf(null), |
| 98 |
() -> c.toArray(null)); |
| 99 |
|
| 100 |
if (!impl.permitsNulls()) { |
| 101 |
assertThrows( |
| 102 |
NullPointerException.class, |
| 103 |
() -> c.add(null)); |
| 104 |
} |
| 105 |
if (!impl.permitsNulls() |
| 106 |
&& Queue.class.isAssignableFrom(impl.klazz())) { |
| 107 |
Queue q = (Queue) c; |
| 108 |
assertThrows( |
| 109 |
NullPointerException.class, |
| 110 |
() -> q.offer(null)); |
| 111 |
} |
| 112 |
if (!impl.permitsNulls() |
| 113 |
&& Deque.class.isAssignableFrom(impl.klazz())) { |
| 114 |
Deque d = (Deque) c; |
| 115 |
assertThrows( |
| 116 |
NullPointerException.class, |
| 117 |
() -> d.addFirst(null), |
| 118 |
() -> d.addLast(null), |
| 119 |
() -> d.offerFirst(null), |
| 120 |
() -> d.offerLast(null), |
| 121 |
() -> d.push(null)); |
| 122 |
} |
| 123 |
} |
| 124 |
|
| 125 |
public void testNoSuchElementExceptions() { |
| 126 |
Collection c = impl.emptyCollection(); |
| 127 |
assertThrows( |
| 128 |
NoSuchElementException.class, |
| 129 |
() -> c.iterator().next()); |
| 130 |
|
| 131 |
if (Queue.class.isAssignableFrom(impl.klazz())) { |
| 132 |
Queue q = (Queue) c; |
| 133 |
assertThrows( |
| 134 |
NoSuchElementException.class, |
| 135 |
() -> q.element(), |
| 136 |
() -> q.remove()); |
| 137 |
} |
| 138 |
if (Deque.class.isAssignableFrom(impl.klazz())) { |
| 139 |
Deque d = (Deque) c; |
| 140 |
assertThrows( |
| 141 |
NoSuchElementException.class, |
| 142 |
() -> d.getFirst(), |
| 143 |
() -> d.getLast(), |
| 144 |
() -> d.removeFirst(), |
| 145 |
() -> d.removeLast(), |
| 146 |
() -> d.pop(), |
| 147 |
() -> d.descendingIterator().next()); |
| 148 |
} |
| 149 |
} |
| 150 |
|
| 151 |
public void testRemoveIf() { |
| 152 |
Collection c = impl.emptyCollection(); |
| 153 |
ThreadLocalRandom rnd = ThreadLocalRandom.current(); |
| 154 |
int n = rnd.nextInt(6); |
| 155 |
for (int i = 0; i < n; i++) c.add(impl.makeElement(i)); |
| 156 |
AtomicReference threwAt = new AtomicReference(null); |
| 157 |
ArrayList survivors = new ArrayList(c); |
| 158 |
ArrayList accepts = new ArrayList(); |
| 159 |
ArrayList rejects = new ArrayList(); |
| 160 |
Predicate randomPredicate = (e) -> { |
| 161 |
assertNull(threwAt.get()); |
| 162 |
switch (rnd.nextInt(3)) { |
| 163 |
case 0: accepts.add(e); return true; |
| 164 |
case 1: rejects.add(e); return false; |
| 165 |
case 2: threwAt.set(e); throw new ArithmeticException(); |
| 166 |
default: throw new AssertionError(); |
| 167 |
} |
| 168 |
}; |
| 169 |
try { |
| 170 |
boolean modified = c.removeIf(randomPredicate); |
| 171 |
if (!modified) { |
| 172 |
assertNull(threwAt.get()); |
| 173 |
assertEquals(n, rejects.size()); |
| 174 |
assertEquals(0, accepts.size()); |
| 175 |
} |
| 176 |
} catch (ArithmeticException ok) {} |
| 177 |
survivors.removeAll(accepts); |
| 178 |
if (n - accepts.size() != c.size()) { |
| 179 |
System.err.println(impl.klazz()); |
| 180 |
System.err.println(c); |
| 181 |
System.err.println(accepts); |
| 182 |
System.err.println(rejects); |
| 183 |
System.err.println(survivors); |
| 184 |
System.err.println(threwAt.get()); |
| 185 |
} |
| 186 |
assertEquals(n - accepts.size(), c.size()); |
| 187 |
assertTrue(c.containsAll(survivors)); |
| 188 |
assertTrue(survivors.containsAll(rejects)); |
| 189 |
for (Object x : accepts) assertFalse(c.contains(x)); |
| 190 |
if (threwAt.get() == null) |
| 191 |
assertEquals(accepts.size() + rejects.size(), n); |
| 192 |
} |
| 193 |
|
| 194 |
// public void testCollectionDebugFail() { |
| 195 |
// fail(impl.klazz().getSimpleName()); |
| 196 |
// } |
| 197 |
} |
