下面列出了java.util.NavigableSet# headSet ( ) 实例代码,或者点击链接到github查看源代码,也可以在右侧发表评论。
/**
* Returns a view of the portion of {@code set} whose elements are contained by {@code range}.
*
* <p>This method delegates to the appropriate methods of {@link NavigableSet} (namely
* {@link NavigableSet#subSet(Object, boolean, Object, boolean) subSet()},
* {@link NavigableSet#tailSet(Object, boolean) tailSet()}, and
* {@link NavigableSet#headSet(Object, boolean) headSet()}) to actually construct the view.
* Consult these methods for a full description of the returned view's behavior.
*
* <p><b>Warning:</b> {@code Range}s always represent a range of values using the values' natural
* ordering. {@code NavigableSet} on the other hand can specify a custom ordering via a
* {@link Comparator}, which can violate the natural ordering. Using this method (or in general
* using {@code Range}) with unnaturally-ordered sets can lead to unexpected and undefined
* behavior.
*
* @since 20.0
*/
@Beta
@GwtIncompatible // NavigableSet
public static <K extends Comparable<? super K>> NavigableSet<K> subSet(NavigableSet<K> set, Range<K> range) {
if (set.comparator() != null && set.comparator() != Ordering.natural()
&& range.hasLowerBound()
&& range.hasUpperBound()) {
checkArgument(set.comparator().compare(range.lowerEndpoint(), range.upperEndpoint()) <= 0, "set is using a custom comparator which is inconsistent with the natural ordering.");
}
if (range.hasLowerBound() && range.hasUpperBound()) {
return set.subSet(
range.lowerEndpoint(),
range.lowerBoundType() == BoundType.CLOSED,
range.upperEndpoint(),
range.upperBoundType() == BoundType.CLOSED);
} else if (range.hasLowerBound()) {
return set.tailSet(range.lowerEndpoint(), range.lowerBoundType() == BoundType.CLOSED);
} else if (range.hasUpperBound()) {
return set.headSet(range.upperEndpoint(), range.upperBoundType() == BoundType.CLOSED);
}
return checkNotNull(set);
}
/**
* headSet returns set with keys in requested range
*/
public void testHeadSetContents() {
NavigableSet set = set5();
SortedSet sm = set.headSet(four);
assertTrue(sm.contains(one));
assertTrue(sm.contains(two));
assertTrue(sm.contains(three));
assertFalse(sm.contains(four));
assertFalse(sm.contains(five));
Iterator i = sm.iterator();
Object k;
k = (Integer)(i.next());
assertEquals(one, k);
k = (Integer)(i.next());
assertEquals(two, k);
k = (Integer)(i.next());
assertEquals(three, k);
assertFalse(i.hasNext());
sm.clear();
assertTrue(sm.isEmpty());
assertEquals(2, set.size());
assertEquals(four, set.first());
}
@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
public void testheadSetRanges(String description, NavigableSet navigableSet) {
NavigableSet subSet = navigableSet.headSet(BigInteger.ONE, true);
// same subset
subSet.headSet(BigInteger.ONE, true);
// slightly smaller
NavigableSet ns = subSet.headSet(BigInteger.ONE, false);
// slight exapansion
assertThrows(() -> {
ns.headSet(BigInteger.ONE, true);
},
IllegalArgumentException.class,
description + ": Expansion should not be allowed");
// much smaller
subSet.headSet(isDescending(subSet) ? BigInteger.TEN : BigInteger.ZERO, true);
}
/**
* headSet returns set with keys in requested range
*/
public void testHeadSetContents() {
NavigableSet set = set5();
SortedSet sm = set.headSet(four);
assertTrue(sm.contains(one));
assertTrue(sm.contains(two));
assertTrue(sm.contains(three));
assertFalse(sm.contains(four));
assertFalse(sm.contains(five));
Iterator i = sm.iterator();
Object k;
k = (Integer)(i.next());
assertEquals(one, k);
k = (Integer)(i.next());
assertEquals(two, k);
k = (Integer)(i.next());
assertEquals(three, k);
assertFalse(i.hasNext());
sm.clear();
assertTrue(sm.isEmpty());
assertEquals(2, set.size());
assertEquals(four, set.first());
}
@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
public void testheadSetRanges(String description, NavigableSet navigableSet) {
NavigableSet subSet = navigableSet.headSet(BigInteger.ONE, true);
// same subset
subSet.headSet(BigInteger.ONE, true);
// slightly smaller
NavigableSet ns = subSet.headSet(BigInteger.ONE, false);
// slight exapansion
assertThrows(() -> {
ns.headSet(BigInteger.ONE, true);
},
IllegalArgumentException.class,
description + ": Expansion should not be allowed");
// much smaller
subSet.headSet(isDescending(subSet) ? BigInteger.TEN : BigInteger.ZERO, true);
}
@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
public void testheadSetRanges(String description, NavigableSet navigableSet) {
NavigableSet subSet = navigableSet.headSet(BigInteger.ONE, true);
// same subset
subSet.headSet(BigInteger.ONE, true);
// slightly smaller
NavigableSet ns = subSet.headSet(BigInteger.ONE, false);
// slight exapansion
assertThrows(() -> {
ns.headSet(BigInteger.ONE, true);
},
IllegalArgumentException.class,
description + ": Expansion should not be allowed");
// much smaller
subSet.headSet(isDescending(subSet) ? BigInteger.TEN : BigInteger.ZERO, true);
}
@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
public void testheadSetRanges(String description, NavigableSet navigableSet) {
NavigableSet subSet = navigableSet.headSet(BigInteger.ONE, true);
// same subset
subSet.headSet(BigInteger.ONE, true);
// slightly smaller
NavigableSet ns = subSet.headSet(BigInteger.ONE, false);
// slight expansion
assertThrowsIAE(() -> {
ns.headSet(BigInteger.ONE, true);
},
description + ": Expansion should not be allowed");
// much smaller
subSet.headSet(isDescending(subSet) ? BigInteger.TEN : BigInteger.ZERO, true);
}
/**
* Returns a view of the portion of {@code set} whose elements are contained by {@code range}.
*
* <p>This method delegates to the appropriate methods of {@link NavigableSet} (namely
* {@link NavigableSet#subSet(Object, boolean, Object, boolean) subSet()},
* {@link NavigableSet#tailSet(Object, boolean) tailSet()}, and
* {@link NavigableSet#headSet(Object, boolean) headSet()}) to actually construct the view.
* Consult these methods for a full description of the returned view's behavior.
*
* <p><b>Warning:</b> {@code Range}s always represent a range of values using the values' natural
* ordering. {@code NavigableSet} on the other hand can specify a custom ordering via a
* {@link Comparator}, which can violate the natural ordering. Using this method (or in general
* using {@code Range}) with unnaturally-ordered sets can lead to unexpected and undefined
* behavior.
*
* @since 20.0
*/
@Beta
@GwtIncompatible // NavigableSet
public static <K extends Comparable<? super K>> NavigableSet<K> subSet(
NavigableSet<K> set, Range<K> range) {
if (set.comparator() != null
&& set.comparator() != Ordering.natural()
&& range.hasLowerBound()
&& range.hasUpperBound()) {
checkArgument(
set.comparator().compare(range.lowerEndpoint(), range.upperEndpoint()) <= 0,
"set is using a custom comparator which is inconsistent with the natural ordering.");
}
if (range.hasLowerBound() && range.hasUpperBound()) {
return set.subSet(
range.lowerEndpoint(),
range.lowerBoundType() == BoundType.CLOSED,
range.upperEndpoint(),
range.upperBoundType() == BoundType.CLOSED);
} else if (range.hasLowerBound()) {
return set.tailSet(range.lowerEndpoint(), range.lowerBoundType() == BoundType.CLOSED);
} else if (range.hasUpperBound()) {
return set.headSet(range.upperEndpoint(), range.upperBoundType() == BoundType.CLOSED);
}
return checkNotNull(set);
}
/**
* headSet returns set with keys in requested range
*/
public void testDescendingHeadSetContents() {
NavigableSet set = dset5();
SortedSet sm = set.headSet(m4);
assertTrue(sm.contains(m1));
assertTrue(sm.contains(m2));
assertTrue(sm.contains(m3));
assertFalse(sm.contains(m4));
assertFalse(sm.contains(m5));
Iterator i = sm.iterator();
Object k;
k = (Integer)(i.next());
assertEquals(m1, k);
k = (Integer)(i.next());
assertEquals(m2, k);
k = (Integer)(i.next());
assertEquals(m3, k);
assertFalse(i.hasNext());
sm.clear();
assertTrue(sm.isEmpty());
assertEquals(2, set.size());
assertEquals(m4, set.first());
}
/**
* headSet returns set with keys in requested range
*/
public void testHeadSetContents() {
NavigableSet set = set5();
SortedSet sm = set.headSet(four);
assertTrue(sm.contains(one));
assertTrue(sm.contains(two));
assertTrue(sm.contains(three));
assertFalse(sm.contains(four));
assertFalse(sm.contains(five));
Iterator i = sm.iterator();
Object k;
k = (Integer)(i.next());
assertEquals(one, k);
k = (Integer)(i.next());
assertEquals(two, k);
k = (Integer)(i.next());
assertEquals(three, k);
assertFalse(i.hasNext());
sm.clear();
assertTrue(sm.isEmpty());
assertEquals(2, set.size());
assertEquals(four, set.first());
}
/**
* headSet returns set with keys in requested range
*/
public void testDescendingHeadSetContents() {
NavigableSet set = dset5();
SortedSet sm = set.headSet(m4);
assertTrue(sm.contains(m1));
assertTrue(sm.contains(m2));
assertTrue(sm.contains(m3));
assertFalse(sm.contains(m4));
assertFalse(sm.contains(m5));
Iterator i = sm.iterator();
Object k;
k = (Integer)(i.next());
assertEquals(m1, k);
k = (Integer)(i.next());
assertEquals(m2, k);
k = (Integer)(i.next());
assertEquals(m3, k);
assertFalse(i.hasNext());
sm.clear();
assertTrue(sm.isEmpty());
assertEquals(2, set.size());
assertEquals(m4, set.first());
}
@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
public void testheadSetRanges(String description, NavigableSet navigableSet) {
NavigableSet subSet = navigableSet.headSet(BigInteger.ONE, true);
// same subset
subSet.headSet(BigInteger.ONE, true);
// slightly smaller
NavigableSet ns = subSet.headSet(BigInteger.ONE, false);
// slight exapansion
assertThrows(() -> {
ns.headSet(BigInteger.ONE, true);
},
IllegalArgumentException.class,
description + ": Expansion should not be allowed");
// much smaller
subSet.headSet(isDescending(subSet) ? BigInteger.TEN : BigInteger.ZERO, true);
}
/**
* headSet returns set with keys in requested range
*/
public void testHeadSetContents() {
NavigableSet set = set5();
SortedSet sm = set.headSet(four);
assertTrue(sm.contains(one));
assertTrue(sm.contains(two));
assertTrue(sm.contains(three));
assertFalse(sm.contains(four));
assertFalse(sm.contains(five));
Iterator i = sm.iterator();
Object k;
k = (Integer)(i.next());
assertEquals(one, k);
k = (Integer)(i.next());
assertEquals(two, k);
k = (Integer)(i.next());
assertEquals(three, k);
assertFalse(i.hasNext());
sm.clear();
assertTrue(sm.isEmpty());
assertEquals(2, set.size());
assertEquals(four, set.first());
}
@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
public void testheadSetRanges(String description, NavigableSet navigableSet) {
NavigableSet subSet = navigableSet.headSet(BigInteger.ONE, true);
// same subset
subSet.headSet(BigInteger.ONE, true);
// slightly smaller
NavigableSet ns = subSet.headSet(BigInteger.ONE, false);
// slight exapansion
assertThrows(() -> {
ns.headSet(BigInteger.ONE, true);
},
IllegalArgumentException.class,
description + ": Expansion should not be allowed");
// much smaller
subSet.headSet(isDescending(subSet) ? BigInteger.TEN : BigInteger.ZERO, true);
}
@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
public void testheadSetRanges(String description, NavigableSet navigableSet) {
NavigableSet subSet = navigableSet.headSet(BigInteger.ONE, true);
// same subset
subSet.headSet(BigInteger.ONE, true);
// slightly smaller
NavigableSet ns = subSet.headSet(BigInteger.ONE, false);
// slight exapansion
assertThrows(() -> {
ns.headSet(BigInteger.ONE, true);
},
IllegalArgumentException.class,
description + ": Expansion should not be allowed");
// much smaller
subSet.headSet(isDescending(subSet) ? BigInteger.TEN : BigInteger.ZERO, true);
}
/**
* Returns a view of the portion of {@code set} whose elements are contained by {@code range}.
*
* <p>This method delegates to the appropriate methods of {@link NavigableSet} (namely
* {@link NavigableSet#subSet(Object, boolean, Object, boolean) subSet()},
* {@link NavigableSet#tailSet(Object, boolean) tailSet()}, and
* {@link NavigableSet#headSet(Object, boolean) headSet()}) to actually construct the view.
* Consult these methods for a full description of the returned view's behavior.
*
* <p><b>Warning:</b> {@code Range}s always represent a range of values using the values' natural
* ordering. {@code NavigableSet} on the other hand can specify a custom ordering via a
* {@link Comparator}, which can violate the natural ordering. Using this method (or in general
* using {@code Range}) with unnaturally-ordered sets can lead to unexpected and undefined
* behavior.
*
* @since 20.0
*/
@Beta
@GwtIncompatible // NavigableSet
public static <K extends Comparable<? super K>> NavigableSet<K> subSet(NavigableSet<K> set, Range<K> range) {
if (set.comparator() != null && set.comparator() != Ordering.natural()
&& range.hasLowerBound()
&& range.hasUpperBound()) {
checkArgument(set.comparator().compare(range.lowerEndpoint(), range.upperEndpoint()) <= 0, "set is using a custom comparator which is inconsistent with the natural ordering.");
}
if (range.hasLowerBound() && range.hasUpperBound()) {
return set.subSet(
range.lowerEndpoint(), range.lowerBoundType() == BoundType.CLOSED,
range.upperEndpoint(), range.upperBoundType() == BoundType.CLOSED);
} else if (range.hasLowerBound()) {
return set.tailSet(range.lowerEndpoint(), range.lowerBoundType() == BoundType.CLOSED);
} else if (range.hasUpperBound()) {
return set.headSet(range.upperEndpoint(), range.upperBoundType() == BoundType.CLOSED);
}
return checkNotNull(set);
}
/**
* headSet returns set with keys in requested range
*/
public void testHeadSetContents() {
NavigableSet set = set5();
SortedSet sm = set.headSet(four);
assertTrue(sm.contains(one));
assertTrue(sm.contains(two));
assertTrue(sm.contains(three));
assertFalse(sm.contains(four));
assertFalse(sm.contains(five));
Iterator i = sm.iterator();
Object k;
k = (Integer)(i.next());
assertEquals(one, k);
k = (Integer)(i.next());
assertEquals(two, k);
k = (Integer)(i.next());
assertEquals(three, k);
assertFalse(i.hasNext());
sm.clear();
assertTrue(sm.isEmpty());
assertEquals(2, set.size());
assertEquals(four, set.first());
}
/**
* headSet returns set with keys in requested range
*/
public void testDescendingHeadSetContents() {
NavigableSet set = dset5();
SortedSet sm = set.headSet(m4);
assertTrue(sm.contains(m1));
assertTrue(sm.contains(m2));
assertTrue(sm.contains(m3));
assertFalse(sm.contains(m4));
assertFalse(sm.contains(m5));
Iterator i = sm.iterator();
Object k;
k = (Integer)(i.next());
assertEquals(m1, k);
k = (Integer)(i.next());
assertEquals(m2, k);
k = (Integer)(i.next());
assertEquals(m3, k);
assertFalse(i.hasNext());
sm.clear();
assertTrue(sm.isEmpty());
assertEquals(2, set.size());
assertEquals(m4, set.first());
}
@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
public void testheadSetRanges(String description, NavigableSet navigableSet) {
NavigableSet subSet = navigableSet.headSet(BigInteger.ONE, true);
// same subset
subSet.headSet(BigInteger.ONE, true);
// slightly smaller
NavigableSet ns = subSet.headSet(BigInteger.ONE, false);
// slight exapansion
assertThrows(() -> {
ns.headSet(BigInteger.ONE, true);
},
IllegalArgumentException.class,
description + ": Expansion should not be allowed");
// much smaller
subSet.headSet(isDescending(subSet) ? BigInteger.TEN : BigInteger.ZERO, true);
}
@Test(dataProvider = "NavigableSet<?>", dataProviderClass = EmptyNavigableSet.class)
public void testheadSetRanges(String description, NavigableSet navigableSet) {
NavigableSet subSet = navigableSet.headSet(BigInteger.ONE, true);
// same subset
subSet.headSet(BigInteger.ONE, true);
// slightly smaller
NavigableSet ns = subSet.headSet(BigInteger.ONE, false);
// slight exapansion
assertThrows(() -> {
ns.headSet(BigInteger.ONE, true);
},
IllegalArgumentException.class,
description + ": Expansion should not be allowed");
// much smaller
subSet.headSet(isDescending(subSet) ? BigInteger.TEN : BigInteger.ZERO, true);
}