Summary: Ctors | Methods | Inherited Methods | [Expand All]

public class

TreeSet

extends AbstractSet<E>
implements NavigableSet<E>

java.lang.Object
↳	java.util.AbstractCollection<E>
	↳	java.util.AbstractSet<E>
		↳	java.util.TreeSet<E>

Class Overview

TreeSet is an implementation of SortedSet. All optional operations (adding and removing) are supported. The elements can be any objects which are comparable to each other either using their natural order or a specified Comparator.

Summary

Public Constructors
	TreeSet() Constructs a new empty instance of `TreeSet` which uses natural ordering.
	TreeSet(Collection<? extends E> collection) Constructs a new instance of `TreeSet` which uses natural ordering and containing the unique elements in the specified collection.
	TreeSet(Comparator<? super E> comparator) Constructs a new empty instance of `TreeSet` which uses the specified comparator.
	TreeSet(SortedSet<E> set) Constructs a new instance of `TreeSet` containing the elements of the specified SortedSet and using the same Comparator.

Public Methods
boolean	add(Object object) Adds the specified object to this `TreeSet`.
boolean	addAll(Collection<? extends E> collection) Adds the objects in the specified collection to this `TreeSet`.
E	ceiling(Object e)
void	clear() Removes all elements from this `TreeSet`, leaving it empty.
Comparator<? super E>	comparator() Returns the comparator used to compare elements in this `TreeSet`.
boolean	contains(Object object) Searches this `TreeSet` for the specified object.
Iterator<E>	descendingIterator() Answers a descending iterator of this set.
NavigableSet<E>	descendingSet() Answers a reverse order view of this set.
E	first() Answers the first element in this TreeSet.
E	floor(Object e)
SortedSet<E>	headSet(Object end) Answers a SortedSet of the specified portion of this TreeSet which contains elements less than the end element.
NavigableSet<E>	headSet(Object end, boolean endInclusive)
E	higher(Object e)
boolean	isEmpty() Returns true if this `TreeSet` has no element, otherwise false.
Iterator<E>	iterator() Returns an Iterator on the elements of this `TreeSet`.
E	last() Answers the last element in this TreeSet.
E	lower(Object e)
E	pollFirst() Deletes and answers the smallest element, or null if the set is empty.
E	pollLast() Deletes and answers the biggest element, or null if the set is empty.
boolean	remove(Object object) Removes an occurrence of the specified object from this `TreeSet`.
int	size() Returns the number of elements in this `TreeSet`.
SortedSet<E>	subSet(Object start, Object end) Answers a SortedSet of the specified portion of this TreeSet which contains elements greater or equal to the start element but less than the end element.
NavigableSet<E>	subSet(Object start, boolean startInclusive, Object end, boolean endInclusive)
NavigableSet<E>	tailSet(Object start, boolean startInclusive)
SortedSet<E>	tailSet(Object start) Answers a SortedSet of the specified portion of this TreeSet which contains elements greater or equal to the start element.

[Expand]

Inherited Methods

From class java.util.AbstractSet

From class java.util.AbstractCollection

boolean	add(E object) Attempts to add `object` to the contents of this `Collection` (optional).
boolean	addAll(Collection<? extends E> collection) Attempts to add all of the objects contained in `collection` to the contents of this `Collection` (optional).
void	clear() Removes all elements from this `Collection`, leaving it empty (optional).
boolean	contains(Object object) Tests whether this `Collection` contains the specified object.
boolean	containsAll(Collection<?> collection) Tests whether this `Collection` contains all objects contained in the specified `Collection`.
boolean	isEmpty() Returns if this `Collection` contains no elements.
abstract Iterator<E>	iterator() Returns an instance of `Iterator` that may be used to access the objects contained by this `Collection`.
boolean	remove(Object object) Removes one instance of the specified object from this `Collection` if one is contained (optional).
boolean	removeAll(Collection<?> collection) Removes all occurrences in this `Collection` of each object in the specified `Collection` (optional).
boolean	retainAll(Collection<?> collection) Removes all objects from this `Collection` that are not also found in the `Collection` passed (optional).
abstract int	size() Returns a count of how many objects this `Collection` contains.
Object[]	toArray() Returns a new array containing all elements contained in this `ArrayList`.
String	toString() Returns the string representation of this `Collection`.

From class java.lang.Object

boolean	equals(Object obj) Indicates whether some other object is "equal to" this one.
final Class<?>	getClass() Returns the runtime class of an object.
int	hashCode() Returns a hash code value for the object.
final void	notify() Wakes up a single thread that is waiting on this object's monitor.
final void	notifyAll() Wakes up all threads that are waiting on this object's monitor.
String	toString() Returns a string representation of the object.
final void	wait(long timeout, int nanos) Causes current thread to wait until another thread invokes the `notify()` method or the `notifyAll()` method for this object, or some other thread interrupts the current thread, or a certain amount of real time has elapsed.
final void	wait(long timeout) Causes current thread to wait until either another thread invokes the `notify()` method or the `notifyAll()` method for this object, or a specified amount of time has elapsed.
final void	wait() Causes current thread to wait until another thread invokes the `notify()` method or the `notifyAll()` method for this object.

From interface java.lang.Iterable

From interface java.util.Collection

abstract boolean	add(E object) Attempts to add `object` to the contents of this `Collection` (optional).
abstract boolean	addAll(Collection<? extends E> collection) Attempts to add all of the objects contained in `Collection` to the contents of this `Collection` (optional).
abstract void	clear() Removes all elements from this `Collection`, leaving it empty (optional).
abstract boolean	contains(Object object) Tests whether this `Collection` contains the specified object.
abstract boolean	containsAll(Collection<?> collection) Tests whether this `Collection` contains all objects contained in the specified `Collection`.
abstract boolean	equals(Object object) Compares the argument to the receiver, and returns true if they represent the same object using a class specific comparison.
abstract int	hashCode() Returns an integer hash code for the receiver.
abstract boolean	isEmpty() Returns if this `Collection` contains no elements.
abstract Iterator<E>	iterator() Returns an instance of `Iterator` that may be used to access the objects contained by this `Collection`.
abstract boolean	remove(Object object) Removes one instance of the specified object from this `Collection` if one is contained (optional).
abstract boolean	removeAll(Collection<?> collection) Removes all occurrences in this `Collection` of each object in the specified `Collection` (optional).
abstract boolean	retainAll(Collection<?> collection) Removes all objects from this `Collection` that are not also found in the `Collection` passed (optional).
abstract int	size() Returns a count of how many objects this `Collection` contains.
abstract <T> T[]	toArray(T[] a) Returns an array containing all of the elements in this collection; the runtime type of the returned array is that of the specified array.
abstract Object[]	toArray() Returns an array containing all of the elements in this collection.

From interface java.util.NavigableSet

abstract E	ceiling(E e) Answers the smallest element bigger than or equal to the specified one, or null if no such element.
abstract Iterator<E>	descendingIterator() Answers a descending iterator of this set.
abstract NavigableSet<E>	descendingSet() Answers a reverse order view of this set.
abstract E	floor(E e) Answers the biggest element less than or equal to the specified one, or null if no such element.
abstract NavigableSet<E>	headSet(E end, boolean endInclusive) Answers a NavigableSet of the specified portion of this set which contains elements less than (or equal to, depends on endInclusive) the end element.
abstract E	higher(E e) Answers the smallest element bigger than the specified one, or null if no such element.
abstract E	lower(E e) Answers the biggest element less than the specified one, or null if no such element.
abstract E	pollFirst() Deletes and answers the smallest element, or null if the set is empty.
abstract E	pollLast() Deletes and answers the biggest element, or null if the set is empty.
abstract NavigableSet<E>	subSet(E start, boolean startInclusive, E end, boolean endInclusive) Answers a NavigableSet of the specified portion of this set which contains elements greater (or equal to, depends on startInclusive) the start element but less than (or equal to, depends on endInclusive) the end element.
abstract NavigableSet<E>	tailSet(E start, boolean startInclusive) Answers a NavigableSet of the specified portion of this set which contains elements greater (or equal to, depends on startInclusive) the start element.

From interface java.util.Set

abstract boolean	add(E object) Adds the specified object to this set.
abstract boolean	addAll(Collection<? extends E> collection) Adds the objects in the specified collection which do not exist yet in this set.
abstract void	clear() Removes all elements from this set, leaving it empty.
abstract boolean	contains(Object object) Searches this set for the specified object.
abstract boolean	containsAll(Collection<?> collection) Searches this set for all objects in the specified collection.
abstract boolean	equals(Object object) Compares the specified object to this set, and returns true if they represent the same object using a class specific comparison.
abstract int	hashCode() Returns the hash code for this set.
abstract boolean	isEmpty() Returns true if this set has no elements.
abstract Iterator<E>	iterator() Returns an iterator on the elements of this set.
abstract boolean	remove(Object object) Removes the specified object from this set.
abstract boolean	removeAll(Collection<?> collection) Removes all objects in the specified collection from this set.
abstract boolean	retainAll(Collection<?> collection) Removes all objects from this set that are not contained in the specified collection.
abstract int	size() Returns the number of elements in this set.
abstract Object[]	toArray() Returns an array containing all elements contained in this set.

From interface java.util.SortedSet

Public Constructors

public TreeSet ()

Constructs a new empty instance of TreeSet which uses natural ordering.

public TreeSet (Collection<? extends E> collection)

Constructs a new instance of TreeSet which uses natural ordering and containing the unique elements in the specified collection.

Parameters

collection	the collection of elements to add.

Throws

ClassCastException	when an element in the collection does not implement the Comparable interface, or the elements in the collection cannot be compared.

public TreeSet (Comparator<? super E> comparator)

Constructs a new empty instance of TreeSet which uses the specified comparator.

Parameters

comparator	the comparator to use.

public TreeSet (SortedSet<E> set)

Constructs a new instance of TreeSet containing the elements of the specified SortedSet and using the same Comparator.

Parameters

set	the SortedSet of elements to add.

Public Methods

public boolean add (Object object)

Adds the specified object to this TreeSet.

Parameters

object	the object to add.

Returns

true when this TreeSet did not already contain the object, false otherwise.

Throws

ClassCastException	when the object cannot be compared with the elements in this `TreeSet`.
NullPointerException	when the object is null and the comparator cannot handle null.

public boolean addAll (Collection<? extends E> collection)

Adds the objects in the specified collection to this TreeSet.

Parameters

collection	the collection of objects to add.

Returns

true if this TreeSet was modified, false otherwise.

Throws

ClassCastException	when an object in the collection cannot be compared with the elements in this `TreeSet`.
NullPointerException	when an object in the collection is null and the comparator cannot handle null.

public E ceiling (Object e)

public void clear ()

Removes all elements from this TreeSet, leaving it empty.

public Comparator<? super E> comparator ()

Returns the comparator used to compare elements in this TreeSet.

Returns

a Comparator or null if the natural ordering is used

public boolean contains (Object object)

Searches this TreeSet for the specified object.

Parameters

object	the object to search for.

Returns

true if object is an element of this TreeSet, false otherwise.

Throws

ClassCastException	when the object cannot be compared with the elements in this `TreeSet`.
NullPointerException	when the object is null and the comparator cannot handle null.

public Iterator<E> descendingIterator ()

Answers a descending iterator of this set.

Returns

the descending iterator

public NavigableSet<E> descendingSet ()

Answers a reverse order view of this set.

Returns

the reverse order view

public E first ()

Answers the first element in this TreeSet.

Returns

the first element

Throws

NoSuchElementException	when this TreeSet is empty

public E floor (Object e)

public SortedSet<E> headSet (Object end)

Answers a SortedSet of the specified portion of this TreeSet which contains elements less than the end element. The returned SortedSet is backed by this TreeSet so changes to one are reflected by the other.

Parameters

end	the end element

Returns

a subset where the elements are less than end

Throws

ClassCastException	when the end object cannot be compared with the elements in this TreeSet
NullPointerException	when the end object is null and the comparator cannot handle null

public NavigableSet<E> headSet (Object end, boolean endInclusive)

public E higher (Object e)

public boolean isEmpty ()

Returns true if this TreeSet has no element, otherwise false.

Returns

true if this TreeSet has no element.

public Iterator<E> iterator ()

Returns an Iterator on the elements of this TreeSet.

Returns

an Iterator on the elements of this TreeSet.

public E last ()

Answers the last element in this TreeSet.

Returns

the last element

Throws

NoSuchElementException	when this TreeSet is empty

public E lower (Object e)

public E pollFirst ()

Deletes and answers the smallest element, or null if the set is empty.

Returns

the smallest element, or null if the set is empty

public E pollLast ()

Deletes and answers the biggest element, or null if the set is empty.

Returns

the biggest element, or null if the set is empty

public boolean remove (Object object)

Removes an occurrence of the specified object from this TreeSet.

Parameters

object	the object to remove.

Returns

true if this TreeSet was modified, false otherwise.

Throws

ClassCastException	when the object cannot be compared with the elements in this `TreeSet`.
NullPointerException	when the object is null and the comparator cannot handle null.

public int size ()

Returns the number of elements in this TreeSet.

Returns

the number of elements in this TreeSet.

public SortedSet<E> subSet (Object start, Object end)

Answers a SortedSet of the specified portion of this TreeSet which contains elements greater or equal to the start element but less than the end element. The returned SortedSet is backed by this TreeSet so changes to one are reflected by the other.

Parameters

start	the start element
end	the end element

Returns

a subset where the elements are greater or equal to start and less than end

Throws

ClassCastException	when the start or end object cannot be compared with the elements in this TreeSet
NullPointerException	when the start or end object is null and the comparator cannot handle null

public NavigableSet<E> subSet (Object start, boolean startInclusive, Object end, boolean endInclusive)

public NavigableSet<E> tailSet (Object start, boolean startInclusive)

public SortedSet<E> tailSet (Object start)

Answers a SortedSet of the specified portion of this TreeSet which contains elements greater or equal to the start element. The returned SortedSet is backed by this TreeSet so changes to one are reflected by the other.

Parameters

start	the start element

Returns

a subset where the elements are greater or equal to start

Throws

ClassCastException	when the start object cannot be compared with the elements in this TreeSet
NullPointerException	when the start object is null and the comparator cannot handle null

Interfaces

Classes

Exceptions

TreeSet

Class Overview

Summary

Public Constructors

public TreeSet ()

public TreeSet (Collection<? extends E> collection)

Parameters

Throws

public TreeSet (Comparator<? super E> comparator)

Parameters

public TreeSet (SortedSet<E> set)

Parameters

Public Methods

public boolean add (Object object)

Parameters

Returns

Throws

public boolean addAll (Collection<? extends E> collection)

Parameters

Returns

Throws

public E ceiling (Object e)

See Also

public void clear ()

See Also

public Comparator<? super E> comparator ()

Returns

public boolean contains (Object object)

Parameters

Returns

Throws

public Iterator<E> descendingIterator ()

Returns

See Also

public NavigableSet<E> descendingSet ()

Returns

See Also

public E first ()

Returns

Throws

public E floor (Object e)

See Also

public SortedSet<E> headSet (Object end)

Parameters

Returns

Throws

public NavigableSet<E> headSet (Object end, boolean endInclusive)

See Also

public E higher (Object e)

See Also

public boolean isEmpty ()

Returns

See Also

public Iterator<E> iterator ()

Returns

See Also

public E last ()

Returns

Throws

public E lower (Object e)

See Also

public E pollFirst ()

Returns

See Also

public E pollLast ()

Returns

See Also

public boolean remove (Object object)

Parameters

Returns

Throws

public int size ()

Returns

public SortedSet<E> subSet (Object start, Object end)

Parameters

Returns

Throws