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 |
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TreeSet()
Constructs a new empty instance of TreeSet which uses natural
ordering.
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TreeSet(Collection<? extends E> collection)
Constructs a new instance of TreeSet which uses natural ordering
and containing the unique elements in the specified collection.
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TreeSet(Comparator<? super E> comparator)
Constructs a new empty instance of TreeSet which uses the
specified comparator.
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TreeSet(SortedSet<E> set)
Constructs a new instance of TreeSet containing the elements of
the specified SortedSet and using the same Comparator.
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Public Methods |
boolean
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add(E object)
Adds the specified object to this TreeSet .
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boolean
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addAll(Collection<? extends E> collection)
Adds the objects in the specified collection to this TreeSet .
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void
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clear()
Removes all elements from this TreeSet , leaving it empty.
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Object
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clone()
Returns a new TreeSet with the same elements, size and comparator
as this TreeSet .
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Comparator<? super E>
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comparator()
Returns the comparator used to compare elements in this TreeSet .
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boolean
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contains(Object object)
Searches this TreeSet for the specified object.
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E
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first()
Returns the first element in this TreeSet .
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SortedSet<E>
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headSet(E end)
Returns a SortedSet of the specified portion of this TreeSet
which contains elements which are all less than the end element.
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boolean
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isEmpty()
Returns true if this TreeSet has no element, otherwise false.
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Iterator<E>
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iterator()
Returns an Iterator on the elements of this TreeSet .
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E
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last()
Returns the last element in this TreeSet .
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boolean
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remove(Object object)
Removes an occurrence of the specified object from this TreeSet .
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int
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size()
Returns the number of elements in this TreeSet .
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SortedSet<E>
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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.
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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.
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[Expand]
Inherited Methods |
From class java.util.AbstractSet
boolean
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equals(Object object)
Compares the specified object to this Set and returns true if they are
equal.
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int
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hashCode()
Returns the hash code for this set.
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boolean
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removeAll(Collection<?> collection)
Removes all occurrences in this collection which are contained in the
specified collection.
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From class java.util.AbstractCollection
boolean
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add(E object)
Attempts to add object to the contents of this
Collection (optional).
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boolean
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addAll(Collection<? extends E> collection)
Attempts to add all of the objects contained in collection
to the contents of this Collection (optional).
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void
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clear()
Removes all elements from this Collection , leaving it empty (optional).
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boolean
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contains(Object object)
Tests whether this Collection contains the specified object.
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boolean
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containsAll(Collection<?> collection)
Tests whether this Collection contains all objects contained in the
specified Collection .
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boolean
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isEmpty()
Returns if this Collection contains no elements.
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abstract
Iterator<E>
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iterator()
Returns an instance of Iterator that may be used to access the
objects contained by this Collection .
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boolean
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remove(Object object)
Removes one instance of the specified object from this Collection if one
is contained (optional).
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boolean
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removeAll(Collection<?> collection)
Removes all occurrences in this Collection of each object in the
specified Collection (optional).
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boolean
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retainAll(Collection<?> collection)
Removes all objects from this Collection that are not also found in the
Collection passed (optional).
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abstract
int
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size()
Returns a count of how many objects this Collection contains.
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<T>
T[]
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toArray(T[] contents)
Returns an array containing all elements contained in this Collection .
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Object[]
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toArray()
Returns a new array containing all elements contained in this Collection .
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String
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toString()
Returns the string representation of this Collection .
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From class java.lang.Object
Object
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clone()
Creates and returns a copy of this Object .
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boolean
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equals(Object o)
Compares this instance with the specified object and indicates if they
are equal.
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void
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finalize()
Is called before the object's memory is being reclaimed by the VM.
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final
Class<? extends Object>
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getClass()
Returns the unique instance of Class which represents this
object's class.
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int
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hashCode()
Returns an integer hash code for this object.
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final
void
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notify()
Causes a thread which is waiting on this object's monitor (by means of
calling one of the wait() methods) to be woken up.
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final
void
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notifyAll()
Causes all threads which are waiting on this object's monitor (by means
of calling one of the wait() methods) to be woken up.
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String
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toString()
Returns a string containing a concise, human-readable description of this
object.
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final
void
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wait(long millis, int nanos)
Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the
specified timeout expires.
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final
void
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wait(long millis)
Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the
specified timeout expires.
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final
void
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wait()
Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object.
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From interface java.lang.Iterable
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From interface java.util.Collection
abstract
boolean
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add(E object)
Attempts to add object to the contents of this
Collection (optional).
|
abstract
boolean
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addAll(Collection<? extends E> collection)
Attempts to add all of the objects contained in Collection
to the contents of this Collection (optional).
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abstract
void
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clear()
Removes all elements from this Collection , leaving it empty (optional).
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abstract
boolean
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contains(Object object)
Tests whether this Collection contains the specified object.
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abstract
boolean
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containsAll(Collection<?> collection)
Tests whether this Collection contains all objects contained in the
specified Collection .
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abstract
boolean
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equals(Object object)
Compares the argument to the receiver, and returns true if they represent
the same object using a class specific comparison.
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abstract
int
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hashCode()
Returns an integer hash code for the receiver.
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abstract
boolean
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isEmpty()
Returns if this Collection contains no elements.
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abstract
Iterator<E>
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iterator()
Returns an instance of Iterator that may be used to access the
objects contained by this Collection .
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abstract
boolean
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remove(Object object)
Removes one instance of the specified object from this Collection if one
is contained (optional).
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abstract
boolean
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removeAll(Collection<?> collection)
Removes all occurrences in this Collection of each object in the
specified Collection (optional).
|
abstract
boolean
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retainAll(Collection<?> collection)
Removes all objects from this Collection that are not also found in the
Collection passed (optional).
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abstract
int
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size()
Returns a count of how many objects this Collection contains.
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abstract
<T>
T[]
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toArray(T[] array)
Returns an array containing all elements contained in this Collection .
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abstract
Object[]
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toArray()
Returns a new array containing all elements contained in this Collection .
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From interface java.util.Set
abstract
boolean
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add(E object)
Adds the specified object to this set.
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abstract
boolean
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addAll(Collection<? extends E> collection)
Adds the objects in the specified collection which do not exist yet in
this set.
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abstract
void
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clear()
Removes all elements from this set, leaving it empty.
|
abstract
boolean
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contains(Object object)
Searches this set for the specified object.
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abstract
boolean
|
containsAll(Collection<?> collection)
Searches this set for all objects in the specified collection.
|
abstract
boolean
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equals(Object object)
Compares the specified object to this set, and returns true if they
represent the same object using a class specific comparison.
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abstract
int
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hashCode()
Returns the hash code for this set.
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abstract
boolean
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isEmpty()
Returns true if this set has no elements.
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abstract
Iterator<E>
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iterator()
Returns an iterator on the elements of this set.
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abstract
boolean
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remove(Object object)
Removes the specified object from this set.
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abstract
boolean
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removeAll(Collection<?> collection)
Removes all objects in the specified collection from this set.
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abstract
boolean
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retainAll(Collection<?> collection)
Removes all objects from this set that are not contained in the specified
collection.
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abstract
int
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size()
Returns the number of elements in this set.
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abstract
<T>
T[]
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toArray(T[] array)
Returns an array containing all elements contained in this set.
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abstract
Object[]
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toArray()
Returns an array containing all elements contained in this set.
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From interface java.util.SortedSet
abstract
Comparator<? super E>
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comparator()
Returns the comparator used to compare elements in this SortedSet .
|
abstract
E
|
first()
Returns the first element in this SortedSet .
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abstract
SortedSet<E>
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headSet(E end)
Returns a SortedSet of the specified portion of this
SortedSet which contains elements less than the end element.
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abstract
E
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last()
Returns the last element in this SortedSet .
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abstract
SortedSet<E>
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subSet(E start, E end)
Returns a SortedSet of the specified portion of this
SortedSet which contains elements greater or equal to the start
element but less than the end element.
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abstract
SortedSet<E>
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tailSet(E start)
Returns a SortedSet of the specified portion of this
SortedSet which contains elements greater or equal to the start
element.
|
|
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
(E 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.
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
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 which are all 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 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
()
Returns the last element in this TreeSet
. The last element is
the highest element.
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.
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 (exclusive). |
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