@Test
public void testMinIndex() {
List<Integer> ints = IntStreamEx.of(new Random(1), 1000, 5, 47).boxed().toList();
long expectedMin = IntStreamEx.ofIndices(ints).minBy(ints::get).getAsInt();
long expectedMax = IntStreamEx.ofIndices(ints).maxBy(ints::get).getAsInt();
long expectedMinString =
IntStreamEx.ofIndices(ints).minBy(i -> String.valueOf(ints.get(i))).getAsInt();
long expectedMaxString =
IntStreamEx.ofIndices(ints).maxBy(i -> String.valueOf(ints.get(i))).getAsInt();
Comparator<Integer> cmp = Comparator.comparing(String::valueOf);
checkCollector(
"minIndex", OptionalLong.of(expectedMin), ints::stream, MoreCollectors.minIndex());
checkCollector(
"maxIndex", OptionalLong.of(expectedMax), ints::stream, MoreCollectors.maxIndex());
checkCollector(
"minIndex", OptionalLong.of(expectedMinString), ints::stream, MoreCollectors.minIndex(cmp));
checkCollector(
"maxIndex", OptionalLong.of(expectedMaxString), ints::stream, MoreCollectors.maxIndex(cmp));
Supplier<Stream<String>> supplier = () -> ints.stream().map(Object::toString);
checkCollector(
"minIndex", OptionalLong.of(expectedMinString), supplier, MoreCollectors.minIndex());
checkCollector(
"maxIndex", OptionalLong.of(expectedMaxString), supplier, MoreCollectors.maxIndex());
checkCollectorEmpty("minIndex", OptionalLong.empty(), MoreCollectors.<String>minIndex());
checkCollectorEmpty("maxIndex", OptionalLong.empty(), MoreCollectors.<String>maxIndex());
}
@Test
public void testToBooleanArray() {
List<Integer> input = IntStreamEx.of(new Random(1), 1000, 1, 100).boxed().toList();
boolean[] expected = new boolean[input.size()];
for (int i = 0; i < expected.length; i++) expected[i] = input.get(i) > 50;
for (StreamExSupplier<Integer> supplier : streamEx(input::stream)) {
assertArrayEquals(
supplier.toString(),
expected,
supplier.get().collect(MoreCollectors.toBooleanArray(x -> x > 50)));
}
}
@Test
public void testGreatest() {
List<Integer> ints = IntStreamEx.of(new Random(1), 1000, 1, 1000).boxed().toList();
List<Integer> sorted = StreamEx.of(ints).sorted().toList();
List<Integer> revSorted = StreamEx.of(ints).reverseSorted().toList();
Comparator<Integer> byString = Comparator.comparing(String::valueOf);
checkShortCircuitCollector(
"least(0)", Collections.emptyList(), 0, ints::stream, MoreCollectors.least(0));
checkCollector("least(5)", sorted.subList(0, 5), ints::stream, MoreCollectors.least(5));
checkCollector("least(20)", sorted.subList(0, 20), ints::stream, MoreCollectors.least(20));
checkCollector("least(MAX)", sorted, ints::stream, MoreCollectors.least(Integer.MAX_VALUE));
checkCollector(
"least(byString, 20)",
StreamEx.of(ints).sorted(byString).limit(20).toList(),
ints::stream,
MoreCollectors.least(byString, 20));
checkShortCircuitCollector(
"greatest(0)", Collections.emptyList(), 0, ints::stream, MoreCollectors.greatest(0));
checkCollector(
"greatest(5)", revSorted.subList(0, 5), ints::stream, MoreCollectors.greatest(5));
checkCollector(
"greatest(20)", revSorted.subList(0, 20), ints::stream, MoreCollectors.greatest(20));
checkCollector(
"greatest(MAX)", revSorted, ints::stream, MoreCollectors.greatest(Integer.MAX_VALUE));
checkCollector(
"greatest(byString, 20)",
StreamEx.of(ints).reverseSorted(byString).limit(20).toList(),
ints::stream,
MoreCollectors.greatest(byString, 20));
Supplier<Stream<Integer>> s = () -> IntStreamEx.range(100).boxed();
checkCollector("1", IntStreamEx.range(1).boxed().toList(), s, MoreCollectors.least(1));
checkCollector("2", IntStreamEx.range(2).boxed().toList(), s, MoreCollectors.least(2));
checkCollector("10", IntStreamEx.range(10).boxed().toList(), s, MoreCollectors.least(10));
checkCollector("100", IntStreamEx.range(100).boxed().toList(), s, MoreCollectors.least(100));
checkCollector("200", IntStreamEx.range(100).boxed().toList(), s, MoreCollectors.least(200));
}
@Test
public void testMaxAll() {
List<String> input = Arrays.asList("a", "bb", "c", "", "cc", "eee", "bb", "ddd");
checkCollector(
"maxAll",
Arrays.asList("eee", "ddd"),
input::stream,
MoreCollectors.maxAll(Comparator.comparingInt(String::length)));
Collector<String, ?, String> maxAllJoin =
MoreCollectors.maxAll(Comparator.comparingInt(String::length), Collectors.joining(","));
checkCollector("maxAllJoin", "eee,ddd", input::stream, maxAllJoin);
checkCollector(
"minAll",
1L,
input::stream,
MoreCollectors.minAll(Comparator.comparingInt(String::length), Collectors.counting()));
checkCollector(
"minAllEmpty",
Arrays.asList(""),
input::stream,
MoreCollectors.minAll(Comparator.comparingInt(String::length)));
checkCollectorEmpty(
"maxAll",
Collections.emptyList(),
MoreCollectors.maxAll(Comparator.comparingInt(String::length)));
checkCollectorEmpty("maxAllJoin", "", maxAllJoin);
List<Integer> ints = IntStreamEx.of(new Random(1), 10000, 1, 1000).boxed().toList();
List<Integer> expectedMax = getMaxAll(ints, Comparator.naturalOrder());
List<Integer> expectedMin = getMaxAll(ints, Comparator.reverseOrder());
Collector<Integer, ?, SimpleEntry<Integer, Long>> downstream =
MoreCollectors.pairing(
MoreCollectors.first(),
Collectors.counting(),
(opt, cnt) -> new AbstractMap.SimpleEntry<>(opt.get(), cnt));
checkCollector("maxAll", expectedMax, ints::stream, MoreCollectors.maxAll(Integer::compare));
checkCollector("minAll", expectedMin, ints::stream, MoreCollectors.minAll());
checkCollector(
"entry",
new SimpleEntry<>(expectedMax.get(0), (long) expectedMax.size()),
ints::stream,
MoreCollectors.maxAll(downstream));
checkCollector(
"entry",
new SimpleEntry<>(expectedMin.get(0), (long) expectedMin.size()),
ints::stream,
MoreCollectors.minAll(downstream));
Integer a = new Integer(1), b = new Integer(1), c = new Integer(1000), d = new Integer(1000);
ints = IntStreamEx.range(10, 100).boxed().append(a, c).prepend(b, d).toList();
for (StreamExSupplier<Integer> supplier : streamEx(ints::stream)) {
List<Integer> list = supplier.get().collect(MoreCollectors.maxAll());
assertEquals(2, list.size());
assertSame(d, list.get(0));
assertSame(c, list.get(1));
list = supplier.get().collect(MoreCollectors.minAll());
assertEquals(2, list.size());
assertSame(b, list.get(0));
assertSame(a, list.get(1));
}
}