/**
* Creates a Tree of the given elements.
*
* @param <T> Component type of the List.
* @param values Zero or more values.
* @return A Tree containing the given values.
* @throws NullPointerException if {@code values} is null
*/
@SuppressWarnings("varargs")
@SafeVarargs
static <T> Tree<T> of(T... values) {
Objects.requireNonNull(values, "values is null");
List<T> list = List.of(values);
return list.isEmpty() ? Empty.instance() : new Node<>(list.head(), list.tail().map(Tree::of));
}
/**
* Returns a new Node containing the given value and having the given children.
*
* @param value A value
* @param children The child nodes, possibly empty
* @param <T> Value type
* @return A new Node instance.
*/
@SuppressWarnings("varargs")
@SafeVarargs
static <T> Node<T> of(T value, Node<T>... children) {
Objects.requireNonNull(children, "children is null");
return new Node<>(value, List.of(children));
}
@Override
protected <T> PriorityQueue<T> of(T element) {
return PriorityQueue.ofAll(toStringComparator(), List.of(element));
}
@Override
@SuppressWarnings("unchecked")
protected final <T> PriorityQueue<T> of(T... elements) {
return PriorityQueue.ofAll(toStringComparator(), List.of(elements));
}
public class PriorityQueueTest extends AbstractTraversableTest {
private final List<Integer> values =
List.of(
3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5, 8, 9, 7, 9, 3, 2, 3, 8, 4, 6, 2, 6, 4, 3, 3, 8, 3, 2, 7,
9, 5, 0, 2, 8, 8, 4, 1, 9, 7, 1, 6, 9, 3, 9, 9, 3, 7, 5, 1, 0);
@Override
protected <T> Collector<T, ArrayList<T>, PriorityQueue<T>> collector() {
return PriorityQueue.collector();
}
@Override
protected <T> PriorityQueue<T> empty() {
return PriorityQueue.empty(toStringComparator());
}
@Override
protected <T> PriorityQueue<T> of(T element) {
return PriorityQueue.ofAll(toStringComparator(), List.of(element));
}
@Override
@SuppressWarnings("unchecked")
protected final <T> PriorityQueue<T> of(T... elements) {
return PriorityQueue.ofAll(toStringComparator(), List.of(elements));
}
@Override
protected <T> PriorityQueue<T> ofAll(Iterable<? extends T> elements) {
return PriorityQueue.ofAll(toStringComparator(), elements);
}
@Override
protected <T> Traversable<T> ofJavaStream(Stream<? extends T> javaStream) {
return PriorityQueue.ofAll(toStringComparator(), javaStream);
}
@Override
protected PriorityQueue<Boolean> ofAll(boolean[] array) {
return PriorityQueue.ofAll(List.ofAll(array));
}
@Override
protected PriorityQueue<Byte> ofAll(byte[] array) {
return PriorityQueue.ofAll(List.ofAll(array));
}
@Override
protected PriorityQueue<Character> ofAll(char[] array) {
return PriorityQueue.ofAll(List.ofAll(array));
}
@Override
protected PriorityQueue<Double> ofAll(double[] array) {
return PriorityQueue.ofAll(List.ofAll(array));
}
@Override
protected PriorityQueue<Float> ofAll(float[] array) {
return PriorityQueue.ofAll(List.ofAll(array));
}
@Override
protected PriorityQueue<Integer> ofAll(int[] array) {
return PriorityQueue.ofAll(List.ofAll(array));
}
@Override
protected PriorityQueue<Long> ofAll(long[] array) {
return PriorityQueue.ofAll(List.ofAll(array));
}
@Override
protected PriorityQueue<Short> ofAll(short[] array) {
return PriorityQueue.ofAll(List.ofAll(array));
}
@Override
protected <T> PriorityQueue<T> tabulate(int n, Function<? super Integer, ? extends T> f) {
return PriorityQueue.tabulate(n, f);
}
@Override
protected <T> PriorityQueue<T> fill(int n, Supplier<? extends T> s) {
return PriorityQueue.fill(n, s);
}
@Override
protected boolean useIsEqualToInsteadOfIsSameAs() {
return true;
}
@Override
protected int getPeekNonNilPerformingAnAction() {
return 1;
}
@Override
protected boolean emptyShouldBeSingleton() {
return false;
}
@Override
protected boolean isOrdered() {
return true;
}
private static SerializableComparator<Object> toStringComparator() {
return (o1, o2) -> String.valueOf(o1).compareTo(String.valueOf(o2));
}
private static Comparator<Integer> composedComparator() {
final Comparator<Integer> bitCountComparator =
(o1, o2) -> Integer.compare(bitCount(o1), bitCount(o2));
return bitCountComparator.thenComparing(naturalComparator());
}
@Test
@Override
public void shouldScanLeftWithNonComparable() {
// The resulting type would need a comparator
}
@Test
@Override
public void shouldScanRightWithNonComparable() {
// The resulting type would need a comparator
}
@Override
public void shouldPreserveSingletonInstanceOnDeserialization() {
// The empty PriorityQueue encapsulates a comparator and therefore cannot be a singleton
}
// -- static narrow
@Test
public void shouldNarrowQueue() {
final PriorityQueue<Double> doubles = of(1.0d);
final PriorityQueue<Number> numbers = PriorityQueue.narrow(doubles);
final int actual = numbers.enqueue(new BigDecimal("2.0")).sum().intValue();
assertThat(actual).isEqualTo(3);
}
// -- toList
@Test
public void toListIsSortedAccordingToComparator() {
final Comparator<Integer> comparator = composedComparator();
final PriorityQueue<Integer> queue = PriorityQueue.ofAll(comparator, values);
assertThat(queue.toList()).isEqualTo(values.sorted(comparator));
}
// -- merge
@Test
public void shouldMergeTwoPriorityQueues() {
final PriorityQueue<Integer> source = of(3, 1, 4, 1, 5);
final PriorityQueue<Integer> target = of(9, 2, 6, 5, 3);
assertThat(source.merge(target)).isEqualTo(of(3, 1, 4, 1, 5, 9, 2, 6, 5, 3));
assertThat(PriorityQueue.of(3).merge(PriorityQueue.of(toStringComparator(), 1)))
.isEqualTo(of(3, 1));
}
// -- distinct
@Test
public void shouldComputeDistinctOfNonEmptyTraversableUsingKeyExtractor() {
final Comparator<String> comparator = (o1, o2) -> Integer.compare(o1.charAt(1), o2.charAt(1));
assertThat(
PriorityQueue.of(comparator, "5c", "1a", "3a", "1a", "2a", "4b", "3b")
.distinct()
.map(s -> s.substring(1)))
.isEqualTo(of("a", "b", "c"));
}
// -- removeAll
@Test
public void shouldRemoveAllElements() {
assertThat(of(3, 1, 4, 1, 5, 9, 2, 6).removeAll(of(1, 9, 1, 2))).isEqualTo(of(3, 4, 5, 6));
}
// -- enqueueAll
@Test
public void shouldEnqueueAllElements() {
assertThat(of(3, 1, 4).enqueueAll(of(1, 5, 9, 2))).isEqualTo(of(3, 1, 4, 1, 5, 9, 2));
}
// -- peek
@Test(expected = NoSuchElementException.class)
public void shouldFailPeekOfEmpty() {
empty().peek();
}
// -- dequeue
@Test
public void shouldDeque() {
assertThat(of(3, 1, 4, 1, 5).dequeue()).isEqualTo(Tuple.of(1, of(3, 4, 1, 5)));
}
@Test(expected = NoSuchElementException.class)
public void shouldFailDequeueOfEmpty() {
empty().dequeue();
}
// -- toPriorityQueue
@Test
public void shouldKeepInstanceOfPriorityQueue() {
final PriorityQueue<Integer> queue = PriorityQueue.of(1, 3, 2);
assertThat(queue.toPriorityQueue()).isSameAs(queue);
}
// -- property based tests
@Test
public void shouldBehaveExactlyLikeAnotherPriorityQueue() {
for (int i = 0; i < 10; i++) {
final Random random = getRandom(-1);
final java.util.PriorityQueue<Integer> mutablePriorityQueue = new java.util.PriorityQueue<>();
javaslang.collection.PriorityQueue<Integer> functionalPriorityQueue =
javaslang.collection.PriorityQueue.empty();
final int size = 100_000;
for (int j = 0; j < size; j++) {
/* Insert */
if (random.nextInt() % 3 == 0) {
assertMinimumsAreEqual(mutablePriorityQueue, functionalPriorityQueue);
final int value = random.nextInt(size) - (size / 2);
mutablePriorityQueue.add(value);
functionalPriorityQueue = functionalPriorityQueue.enqueue(value);
}
assertMinimumsAreEqual(mutablePriorityQueue, functionalPriorityQueue);
/* Delete */
if (random.nextInt() % 5 == 0) {
if (!mutablePriorityQueue.isEmpty()) {
mutablePriorityQueue.poll();
}
if (!functionalPriorityQueue.isEmpty()) {
functionalPriorityQueue = functionalPriorityQueue.tail();
}
assertMinimumsAreEqual(mutablePriorityQueue, functionalPriorityQueue);
}
}
final Collection<Integer> oldValues =
mutablePriorityQueue.stream().sorted().collect(toList());
final Collection<Integer> newValues = functionalPriorityQueue.toJavaList();
assertThat(oldValues).isEqualTo(newValues);
}
}
private void assertMinimumsAreEqual(
java.util.PriorityQueue<Integer> oldQueue, PriorityQueue<Integer> newQueue) {
assertThat(oldQueue.isEmpty()).isEqualTo(newQueue.isEmpty());
if (!newQueue.isEmpty()) {
assertThat(oldQueue.peek()).isEqualTo(newQueue.head());
}
}
}