@Test
public void testEnumIterator() {
@SuppressWarnings("unchecked")
Iterator<String> iterator =
CollectionUtil.iterator((Enumeration) new StringTokenizer("foo, bar, baz", ", "));
int count = 0;
for (Object stringObject : stringObjects) {
assertTrue(iterator.hasNext());
assertEquals(stringObject, iterator.next());
try {
iterator.remove();
fail("Enumeration has no remove method, iterator.remove() must throw exception");
} catch (UnsupportedOperationException expected) {
}
count++;
}
assertEquals(3, count);
assertFalse(iterator.hasNext());
try {
iterator.next();
fail("Iterator has more elements than enumeration");
} catch (NoSuchElementException expected) {
}
}
@Test
public void testReverseOrderRandomIntegers() {
Comparator<Integer> naturalOrder = new NaturalOrder<Integer>();
Comparator<Integer> reverse = CollectionUtil.reverseOrder(naturalOrder);
Random random = new Random(243249878l); // Stable "random" sequence
for (int i = 0; i < 65536; i++) {
// Verified to be ~ 50/50 lt/gt
int integer = random.nextInt();
int integerToo = random.nextInt();
assertEquals(0, reverse.compare(integer, integer));
assertEquals(0, reverse.compare(integerToo, integerToo));
int natural = naturalOrder.compare(integer, integerToo);
if (natural == 0) {
// Actually never hits, but eq case is tested above
assertEquals(0, reverse.compare(integer, integerToo));
} else if (natural < 0) {
assertTrue(reverse.compare(integer, integerToo) > 0);
} else {
assertTrue(reverse.compare(integer, integerToo) < 0);
}
}
}
@Test(expected = ArrayStoreException.class)
public void testMergeArraysObjectIllegalType() {
String[] strings = {"foo", "bar", "baz"};
Integer[] integers = {1, 2, 3}; // Integer not assignable to String
CollectionUtil.mergeArrays(strings, integers);
}
@Test(expected = ArrayStoreException.class)
public void testMergeArraysNativeIllegalType() {
char[] chars = {'a', 'b', 'c'};
int[] integers = {1, 2, 3}; // Integer not assignable to String
CollectionUtil.mergeArrays(chars, integers);
}
@Test
public void testArrayIterator() {
Iterator<String> iterator = CollectionUtil.iterator(new String[] {"foo", "bar", "baz"});
int count = 0;
for (Object stringObject : stringObjects) {
assertTrue(iterator.hasNext());
assertEquals(stringObject, iterator.next());
try {
iterator.remove();
fail("Array have fixed length, iterator.remove() must throw exception");
} catch (UnsupportedOperationException expected) {
}
count++;
}
assertEquals(3, count);
assertFalse(iterator.hasNext());
try {
iterator.next();
fail("Iterator has more elements than array");
} catch (NoSuchElementException expected) {
}
}
@Test
public void testMergeArraysObjectAssignable() {
Integer[] integers = {1, 2, 3}; // Integer assignable to Object
Object[] merged = (Object[]) CollectionUtil.mergeArrays(stringObjects, integers);
assertArrayEquals(new Object[] {"foo", "bar", "baz", 1, 2, 3}, merged);
}
@Ignore("For development only")
@Test
@SuppressWarnings({"UnusedDeclaration"})
public void testGenerify() {
List list = Collections.singletonList("foo");
@SuppressWarnings({"unchecked"})
Set set = new HashSet(list);
List<String> strs0 = CollectionUtil.generify(list, String.class);
List<Object> objs0 = CollectionUtil.generify(list, String.class);
// List<String> strs01 = CollectionUtil.generify(list, Object.class); // Not okay
try {
List<String> strs1 =
CollectionUtil.generify(set, String.class); // Not ok, runtime CCE unless set is null
} catch (RuntimeException e) {
e.printStackTrace();
}
try {
ArrayList<String> strs01 =
CollectionUtil.generify(list, String.class); // Not ok, runtime CCE unless list is null
} catch (RuntimeException e) {
e.printStackTrace();
}
Set<String> setstr1 = CollectionUtil.generify(set, String.class);
Set<Object> setobj1 = CollectionUtil.generify(set, String.class);
try {
Set<Object> setobj44 =
CollectionUtil.generify(list, String.class); // Not ok, runtime CCE unless list is null
} catch (RuntimeException e) {
e.printStackTrace();
}
List<String> strs2 = CollectionUtil.<List<String>, String>generify2(list);
List<Object> objs2 = CollectionUtil.<List<Object>, String>generify2(list);
// List<String> morestrs = CollectionUtil.<List<Object>, String>generify2(list); // Not
// ok
try {
List<String> strs3 =
CollectionUtil.<List<String>, String>generify2(
set); // Not ok, runtime CCE unless set is null
} catch (RuntimeException e) {
e.printStackTrace();
}
}
@Test
public void testMergeArraysNative() {
char[] chars = {'a', 'b', 'c'};
char[] more = {'x', 'y', 'z'};
char[] merged = (char[]) CollectionUtil.mergeArrays(chars, more);
assertArrayEquals(new char[] {'a', 'b', 'c', 'x', 'y', 'z'}, merged);
}
@Test
public void testSelectRandomSubset() {
ArrayList<Integer> list = new ArrayList<Integer>();
for (int i = 0; i < 100; i++) {
list.add(i);
}
for (int i = 0; i < 10; i++) {
List<Integer> subset = CollectionUtil.selectRandomSubset(list, 10);
// System.out.println(StringUtil.toString(subset));
assertTrue("length == 10", subset.size() == 10);
}
}
@Test
public void testReverseOrder() {
Comparator<String> naturalOrder = new NaturalOrder<String>();
Comparator<String> reverse = CollectionUtil.reverseOrder(naturalOrder);
assertNotNull(reverse);
assertEquals(0, naturalOrder.compare("foo", "foo"));
assertEquals(0, reverse.compare("foo", "foo"));
assertTrue(naturalOrder.compare("bar", "baz") < 0);
assertTrue(reverse.compare("bar", "baz") > 0);
assertTrue(naturalOrder.compare("baz", "bar") > 0);
assertTrue(reverse.compare("baz", "bar") < 0);
}
@Test
public void testArrayIteratorRange() {
Iterator<String> iterator =
CollectionUtil.iterator(new String[] {"foo", "bar", "baz", "xyzzy"}, 1, 2);
for (int i = 1; i < 3; i++) {
assertTrue(iterator.hasNext());
assertEquals(stringObjects[i], iterator.next());
try {
iterator.remove();
fail("Array has no remove method, iterator.remove() must throw exception");
} catch (UnsupportedOperationException expected) {
}
}
assertFalse(iterator.hasNext());
try {
iterator.next();
fail("Iterator has more elements than array range");
} catch (NoSuchElementException expected) {
}
}
@Test
public void testArrayListIteratorRange() {
assertCorrectListIterator(
CollectionUtil.iterator(new String[] {"foo", "bar", "baz", "boo"}, 1, 2),
new String[] {"bar", "baz"});
}
@Test(expected = IndexOutOfBoundsException.class)
public void testMergeArraysObjectNegativeSecondLength() {
CollectionUtil.mergeArrays(stringObjects, 1, 2, integerObjects, 2, -1);
}
@Test(expected = IndexOutOfBoundsException.class)
public void testMergeArraysObjectBadSecondOffset() {
CollectionUtil.mergeArrays(stringObjects, 1, 2, integerObjects, 4, 1);
}
@Test
public void testMergeArraysObjectOffset() {
Object[] merged =
(Object[]) CollectionUtil.mergeArrays(stringObjects, 1, 2, integerObjects, 2, 1);
assertArrayEquals(new Object[] {"bar", "baz", 3}, merged);
}
@Test
public void testSubArrayObject() {
String[] strings = CollectionUtil.subArray(new String[] {"foo", "bar", "baz", "xyzzy"}, 1, 2);
assertArrayEquals(new String[] {"bar", "baz"}, strings);
}
@Test
public void testSubArrayNative() {
int[] numbers = (int[]) CollectionUtil.subArray(new int[] {1, 2, 3, 4, 5}, 1, 3);
assertArrayEquals(new int[] {2, 3, 4}, numbers);
}
@Test(expected = IllegalArgumentException.class)
public void testReverseOrderNull() {
CollectionUtil.reverseOrder(null);
}
@Test(expected = IllegalArgumentException.class)
public void testArrayIteratorRangeBadLength() {
CollectionUtil.iterator(stringObjects, 1, stringObjects.length);
}
@Test(expected = IllegalArgumentException.class)
public void testArrayIteratorRangeNull() {
CollectionUtil.iterator(null, 0, 0);
}
@Test(expected = IllegalArgumentException.class)
public void testEnumIteratorNull() {
CollectionUtil.iterator((Enumeration<Object>) null);
}
@Test
public void testArrayListIterator() {
assertCorrectListIterator(
CollectionUtil.iterator(new String[] {"foo", "bar", "baz"}), stringObjects);
}
@Test(expected = IllegalArgumentException.class)
public void testArrayIteratorNull() {
CollectionUtil.iterator((Object[]) null);
}