LinkedHashSet

Class Overview

LinkedHashSet is a variant of HashSet. Its entries are kept in a doubly-linked list. The iteration order is the order in which entries were inserted.

Null elements are allowed, and all the optional Set operations are supported.

Like HashSet, LinkedHashSet is not thread safe, so access by multiple threads must be synchronized by an external mechanism such as


        
         
          )">synchronizedSet(Set)

Summary

Public Constructors
	LinkedHashSet () Constructs a new empty instance of `LinkedHashSet` .
	LinkedHashSet (int capacity) Constructs a new instance of `LinkedHashSet` with the specified capacity.
	LinkedHashSet (int capacity, float loadFactor) Constructs a new instance of `LinkedHashSet` with the specified capacity and load factor.
	)">LinkedHashSet ( Collection <? extends E> collection) Constructs a new instance of `LinkedHashSet` containing the unique elements in the specified collection.

Public Constructors

LinkedHashSet ()

Constructs a new empty instance of


           LinkedHashSet

LinkedHashSet (int capacity)

Constructs a new instance of


           LinkedHashSet

with the specified capacity.

LinkedHashSet (int capacity, float loadFactor)

Constructs a new instance of


           LinkedHashSet

with the specified capacity and load factor.

)">LinkedHashSet ( Collection <? extends E> collection)

Constructs a new instance of


           LinkedHashSet

containing the unique elements in the specified collection.

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Inherited Methods

From class java.util.HashSet

boolean	add (E object) Adds the specified object to this `HashSet` if not already present.
void	clear () Removes all elements from this `HashSet` , leaving it empty.
Object	clone () Returns a new `HashSet` with the same elements and size as this `HashSet` .
boolean	contains ( Object object) Searches this `HashSet` for the specified object.
boolean	isEmpty () Returns true if this `HashSet` has no elements, false otherwise.
Iterator <E>	iterator () Returns an Iterator on the elements of this `HashSet` .
boolean	remove ( Object object) Removes the specified object from this `HashSet` .
int	size () Returns the number of elements in this `HashSet` .

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.
<T> T[]	toArray (T[] contents) Returns an array containing all elements contained in this `Collection` .
Object[]	toArray () Returns a new array containing all elements contained in this `Collection` .
String	toString () Returns the string representation of this `Collection` .

From class java.lang.Object

Object	clone () Creates and returns a copy of this `Object` .
boolean	equals ( Object o) Compares this instance with the specified object and indicates if they are equal.
void	finalize () Invoked when the garbage collector has detected that this instance is no longer reachable.
final Class <?>	getClass () Returns the unique instance of `Class` that represents this object's class.
int	hashCode () Returns an integer hash code for this object.
final void	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.
final void	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.
String	toString () Returns a string containing a concise, human-readable description of this object.
final void	wait () Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object.
final void	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.
final void	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.

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[] array) Returns an array containing all elements contained in this `Collection` .
abstract Object[]	toArray () Returns a new array containing all elements contained in this `Collection` .

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 <T> T[]	toArray (T[] array) Returns an array containing all elements contained in this set.
abstract Object[]	toArray () Returns an array containing all elements contained in this set.

Public Constructors

public LinkedHashSet ()

Added in API level 1

Constructs a new empty instance of LinkedHashSet .

public LinkedHashSet (int capacity)

Added in API level 1

Constructs a new instance of LinkedHashSet with the specified capacity.

Parameters

capacity	the initial capacity of this `LinkedHashSet` .

public LinkedHashSet (int capacity, float loadFactor)

Added in API level 1

Constructs a new instance of LinkedHashSet with the specified capacity and load factor.

Parameters

capacity	the initial capacity.
loadFactor	the initial load factor.

)">

public LinkedHashSet ( Collection <? extends E> collection)

Added in API level 1

Constructs a new instance of LinkedHashSet containing the unique elements in the specified collection.

Parameters

collection	the collection of elements to add.

java.lang.Object
↳	java.util.AbstractCollection <E>
	↳	java.util.AbstractSet <E>
		↳	java.util.HashSet <E>
			↳	java.util.LinkedHashSet<E>

Results

Interfaces

Classes

Enums

Exceptions

Errors

Class Overview

Summary

Public Constructors

public LinkedHashSet ()

public LinkedHashSet (int capacity)

Parameters

public LinkedHashSet (int capacity, float loadFactor)

Parameters

public LinkedHashSet ( Collection <? extends E> collection)

Parameters