/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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*/
/*
* This file is available under and governed by the GNU General Public
* License version 2 only, as published by the Free Software Foundation.
* However, the following notice accompanied the original version of this
* file:
*
* 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.
*/
import java.util.Arrays;
import java.util.Collection;
import java.util.Comparator;
import java.util.Iterator;
import java.util.NoSuchElementException;
import java.util.PriorityQueue;
import java.util.Queue;
import junit.framework.Test;
import junit.framework.TestSuite;
public class PriorityQueueTest extends JSR166TestCase {
public static void main(String[] args) {
main(suite(), args);
}
public static Test suite() {
class Implementation implements CollectionImplementation {
public Class<?> klazz() { return PriorityQueue.class; }
public Collection emptyCollection() { return new PriorityQueue(); }
public Object makeElement(int i) { return i; }
public boolean isConcurrent() { return false; }
public boolean permitsNulls() { return false; }
}
return newTestSuite(PriorityQueueTest.class,
CollectionTest.testSuite(new Implementation()));
}
static class MyReverseComparator implements Comparator {
public int compare(Object x, Object y) {
return ((Comparable)y).compareTo(x);
}
}
/**
* Returns a new queue of given size containing consecutive
* Integers 0 ... n - 1.
*/
private PriorityQueue<Integer> populatedQueue(int n) {
PriorityQueue<Integer> q = new PriorityQueue<Integer>(n);
assertTrue(q.isEmpty());
for (int i = n - 1; i >= 0; i -= 2)
assertTrue(q.offer(new Integer(i)));
for (int i = (n & 1); i < n; i += 2)
assertTrue(q.offer(new Integer(i)));
assertFalse(q.isEmpty());
assertEquals(n, q.size());
assertEquals((Integer) 0, q.peek());
return q;
}
/**
* A new queue has unbounded capacity
*/
public void testConstructor1() {
assertEquals(0, new PriorityQueue(SIZE).size());
}
/**
* Constructor throws IAE if capacity argument nonpositive
*/
public void testConstructor2() {
try {
new PriorityQueue(0);
shouldThrow();
} catch (IllegalArgumentException success) {}
}
/**
* Initializing from null Collection throws NPE
*/
public void testConstructor3() {
try {
new PriorityQueue((Collection)null);
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* Initializing from Collection of null elements throws NPE
*/
public void testConstructor4() {
try {
new PriorityQueue(Arrays.asList(new Integer[SIZE]));
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* Initializing from Collection with some null elements throws NPE
*/
public void testConstructor5() {
Integer[] ints = new Integer[SIZE];
for (int i = 0; i < SIZE - 1; ++i)
ints[i] = new Integer(i);
try {
new PriorityQueue(Arrays.asList(ints));
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* Queue contains all elements of collection used to initialize
*/
public void testConstructor6() {
Integer[] ints = new Integer[SIZE];
for (int i = 0; i < SIZE; ++i)
ints[i] = new Integer(i);
PriorityQueue q = new PriorityQueue(Arrays.asList(ints));
for (int i = 0; i < SIZE; ++i)
assertEquals(ints[i], q.poll());
}
/**
* The comparator used in constructor is used
*/
public void testConstructor7() {
MyReverseComparator cmp = new MyReverseComparator();
PriorityQueue q = new PriorityQueue(SIZE, cmp);
assertEquals(cmp, q.comparator());
Integer[] ints = new Integer[SIZE];
for (int i = 0; i < SIZE; ++i)
ints[i] = new Integer(i);
q.addAll(Arrays.asList(ints));
for (int i = SIZE - 1; i >= 0; --i)
assertEquals(ints[i], q.poll());
}
/**
* isEmpty is true before add, false after
*/
public void testEmpty() {
PriorityQueue q = new PriorityQueue(2);
assertTrue(q.isEmpty());
q.add(new Integer(1));
assertFalse(q.isEmpty());
q.add(new Integer(2));
q.remove();
q.remove();
assertTrue(q.isEmpty());
}
/**
* size changes when elements added and removed
*/
public void testSize() {
PriorityQueue q = populatedQueue(SIZE);
for (int i = 0; i < SIZE; ++i) {
assertEquals(SIZE - i, q.size());
q.remove();
}
for (int i = 0; i < SIZE; ++i) {
assertEquals(i, q.size());
q.add(new Integer(i));
}
}
/**
* offer(null) throws NPE
*/
public void testOfferNull() {
PriorityQueue q = new PriorityQueue(1);
try {
q.offer(null);
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* add(null) throws NPE
*/
public void testAddNull() {
PriorityQueue q = new PriorityQueue(1);
try {
q.add(null);
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* Offer of comparable element succeeds
*/
public void testOffer() {
PriorityQueue q = new PriorityQueue(1);
assertTrue(q.offer(zero));
assertTrue(q.offer(one));
}
/**
* Offer of non-Comparable throws CCE
*/
public void testOfferNonComparable() {
PriorityQueue q = new PriorityQueue(1);
try {
q.offer(new Object());
shouldThrow();
} catch (ClassCastException success) {
assertTrue(q.isEmpty());
assertEquals(0, q.size());
assertNull(q.poll());
}
}
/**
* add of comparable succeeds
*/
public void testAdd() {
PriorityQueue q = new PriorityQueue(SIZE);
for (int i = 0; i < SIZE; ++i) {
assertEquals(i, q.size());
assertTrue(q.add(new Integer(i)));
}
}
/**
* addAll(null) throws NPE
*/
public void testAddAll1() {
PriorityQueue q = new PriorityQueue(1);
try {
q.addAll(null);
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* addAll of a collection with null elements throws NPE
*/
public void testAddAll2() {
PriorityQueue q = new PriorityQueue(SIZE);
try {
q.addAll(Arrays.asList(new Integer[SIZE]));
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* addAll of a collection with any null elements throws NPE after
* possibly adding some elements
*/
public void testAddAll3() {
PriorityQueue q = new PriorityQueue(SIZE);
Integer[] ints = new Integer[SIZE];
for (int i = 0; i < SIZE - 1; ++i)
ints[i] = new Integer(i);
try {
q.addAll(Arrays.asList(ints));
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* Queue contains all elements of successful addAll
*/
public void testAddAll5() {
Integer[] empty = new Integer[0];
Integer[] ints = new Integer[SIZE];
for (int i = 0; i < SIZE; ++i)
ints[i] = new Integer(SIZE - 1 - i);
PriorityQueue q = new PriorityQueue(SIZE);
assertFalse(q.addAll(Arrays.asList(empty)));
assertTrue(q.addAll(Arrays.asList(ints)));
for (int i = 0; i < SIZE; ++i)
assertEquals(new Integer(i), q.poll());
}
/**
* poll succeeds unless empty
*/
public void testPoll() {
PriorityQueue q = populatedQueue(SIZE);
for (int i = 0; i < SIZE; ++i) {
assertEquals(i, q.poll());
}
assertNull(q.poll());
}
/**
* peek returns next element, or null if empty
*/
public void testPeek() {
PriorityQueue q = populatedQueue(SIZE);
for (int i = 0; i < SIZE; ++i) {
assertEquals(i, q.peek());
assertEquals(i, q.poll());
assertTrue(q.peek() == null ||
!q.peek().equals(i));
}
assertNull(q.peek());
}
/**
* element returns next element, or throws NSEE if empty
*/
public void testElement() {
PriorityQueue q = populatedQueue(SIZE);
for (int i = 0; i < SIZE; ++i) {
assertEquals(i, q.element());
assertEquals(i, q.poll());
}
try {
q.element();
shouldThrow();
} catch (NoSuchElementException success) {}
}
/**
* remove removes next element, or throws NSEE if empty
*/
public void testRemove() {
PriorityQueue q = populatedQueue(SIZE);
for (int i = 0; i < SIZE; ++i) {
assertEquals(i, q.remove());
}
try {
q.remove();
shouldThrow();
} catch (NoSuchElementException success) {}
}
/**
* remove(x) removes x and returns true if present
*/
public void testRemoveElement() {
PriorityQueue q = populatedQueue(SIZE);
for (int i = 1; i < SIZE; i += 2) {
assertTrue(q.contains(i));
assertTrue(q.remove(i));
assertFalse(q.contains(i));
assertTrue(q.contains(i - 1));
}
for (int i = 0; i < SIZE; i += 2) {
assertTrue(q.contains(i));
assertTrue(q.remove(i));
assertFalse(q.contains(i));
assertFalse(q.remove(i + 1));
assertFalse(q.contains(i + 1));
}
assertTrue(q.isEmpty());
}
/**
* contains(x) reports true when elements added but not yet removed
*/
public void testContains() {
PriorityQueue q = populatedQueue(SIZE);
for (int i = 0; i < SIZE; ++i) {
assertTrue(q.contains(new Integer(i)));
q.poll();
assertFalse(q.contains(new Integer(i)));
}
}
/**
* clear removes all elements
*/
public void testClear() {
PriorityQueue q = populatedQueue(SIZE);
q.clear();
assertTrue(q.isEmpty());
assertEquals(0, q.size());
q.add(new Integer(1));
assertFalse(q.isEmpty());
q.clear();
assertTrue(q.isEmpty());
}
/**
* containsAll(c) is true when c contains a subset of elements
*/
public void testContainsAll() {
PriorityQueue q = populatedQueue(SIZE);
PriorityQueue p = new PriorityQueue(SIZE);
for (int i = 0; i < SIZE; ++i) {
assertTrue(q.containsAll(p));
assertFalse(p.containsAll(q));
p.add(new Integer(i));
}
assertTrue(p.containsAll(q));
}
/**
* retainAll(c) retains only those elements of c and reports true if changed
*/
public void testRetainAll() {
PriorityQueue q = populatedQueue(SIZE);
PriorityQueue p = populatedQueue(SIZE);
for (int i = 0; i < SIZE; ++i) {
boolean changed = q.retainAll(p);
if (i == 0)
assertFalse(changed);
else
assertTrue(changed);
assertTrue(q.containsAll(p));
assertEquals(SIZE - i, q.size());
p.remove();
}
}
/**
* removeAll(c) removes only those elements of c and reports true if changed
*/
public void testRemoveAll() {
for (int i = 1; i < SIZE; ++i) {
PriorityQueue q = populatedQueue(SIZE);
PriorityQueue p = populatedQueue(i);
assertTrue(q.removeAll(p));
assertEquals(SIZE - i, q.size());
for (int j = 0; j < i; ++j) {
Integer x = (Integer)(p.remove());
assertFalse(q.contains(x));
}
}
}
/**
* toArray contains all elements
*/
public void testToArray() {
PriorityQueue q = populatedQueue(SIZE);
Object[] o = q.toArray();
Arrays.sort(o);
for (int i = 0; i < o.length; i++)
assertSame(o[i], q.poll());
}
/**
* toArray(a) contains all elements
*/
public void testToArray2() {
PriorityQueue<Integer> q = populatedQueue(SIZE);
Integer[] ints = new Integer[SIZE];
Integer[] array = q.toArray(ints);
assertSame(ints, array);
Arrays.sort(ints);
for (int i = 0; i < ints.length; i++)
assertSame(ints[i], q.poll());
}
/**
* iterator iterates through all elements
*/
public void testIterator() {
PriorityQueue q = populatedQueue(SIZE);
Iterator it = q.iterator();
int i;
for (i = 0; it.hasNext(); i++)
assertTrue(q.contains(it.next()));
assertEquals(i, SIZE);
assertIteratorExhausted(it);
}
/**
* iterator of empty collection has no elements
*/
public void testEmptyIterator() {
assertIteratorExhausted(new PriorityQueue().iterator());
}
/**
* iterator.remove removes current element
*/
public void testIteratorRemove() {
final PriorityQueue q = new PriorityQueue(3);
q.add(new Integer(2));
q.add(new Integer(1));
q.add(new Integer(3));
Iterator it = q.iterator();
it.next();
it.remove();
it = q.iterator();
assertEquals(it.next(), new Integer(2));
assertEquals(it.next(), new Integer(3));
assertFalse(it.hasNext());
}
/**
* toString contains toStrings of elements
*/
public void testToString() {
PriorityQueue q = populatedQueue(SIZE);
String s = q.toString();
for (int i = 0; i < SIZE; ++i) {
assertTrue(s.contains(String.valueOf(i)));
}
}
/**
* A deserialized serialized queue has same elements
*/
public void testSerialization() throws Exception {
Queue x = populatedQueue(SIZE);
Queue y = serialClone(x);
assertNotSame(x, y);
assertEquals(x.size(), y.size());
while (!x.isEmpty()) {
assertFalse(y.isEmpty());
assertEquals(x.remove(), y.remove());
}
assertTrue(y.isEmpty());
}
}