java.util.TreeSet<E>
TreeSet is an implementation of SortedSet. All optional operations are
supported, adding and removing. The elements can be any objects which are
comparable to each other either using their natural order or a specified
Comparator.
Summary
Public Constructors
Public Methods
add,
addAll,
clear,
contains,
containsAll,
isEmpty,
iterator,
remove,
removeAll,
retainAll,
size,
toArray,
toArray,
toString
clone,
equals,
finalize,
getClass,
hashCode,
notify,
notifyAll,
toString,
wait,
wait,
wait
add,
addAll,
clear,
contains,
containsAll,
equals,
hashCode,
isEmpty,
iterator,
remove,
removeAll,
retainAll,
size,
toArray,
toArray
Methods inherited
from interface
java.util.Set
add,
addAll,
clear,
contains,
containsAll,
equals,
hashCode,
isEmpty,
iterator,
remove,
removeAll,
retainAll,
size,
toArray,
toArray
Details
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
|
public
TreeSet(SortedSet<E> set)
Constructs a new instance of TreeSet containing the elements in the
specified SortedSet and using the same Comparator.
Parameters
set
| the SortedSet of elements to add
|
Public Methods
public
boolean
add(E object)
Adds the specified object to this TreeSet.
Returns
- true when this TreeSet did not already contain the object, false
otherwise
public
boolean
addAll(Collection<? extends E> collection)
Adds the objects in the specified Collection to this TreeSet.
Parameters
collection
| the Collection of objects |
Returns
- true if this TreeSet is 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
void
clear()
Removes all elements from this TreeSet, leaving it empty.
public
Object
clone()
Returns a new TreeSet with the same elements, size and comparator as this
TreeSet.
Returns
- a shallow copy of this TreeSet
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
public
E
first()
Returns the first element in this TreeSet.
public
SortedSet<E>
headSet(E end)
Returns 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.
Returns
- a subset where the elements are less than
end
public
boolean
isEmpty()
Returns if this TreeSet has no elements, a size of zero.
Returns
- true if this TreeSet has no elements, false otherwise
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()
Returns the last element in this TreeSet.
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 is modified, false otherwise
public
int
size()
Returns the number of elements in this TreeSet.
Returns
- the number of elements in this TreeSet
public
SortedSet<E>
subSet(E start, E end)
Returns 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
SortedSet<E>
tailSet(E start)
Returns 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.
Returns
- a subset where the elements are greater or equal to
start