java.util

Class HashSet<E>

java.lang.Object

java.util.AbstractCollection<E>

java.util.AbstractSet<E>

java.util.HashSet<E>

Type Parameters:

E - element type.

All Implemented Interfaces:

Serializable, Cloneable, Iterable<E>, Collection<E>, Set<E>

Direct Known Subclasses:

LinkedHashSet

public class HashSet<E>
extends AbstractSet<E>
implements Set<E>, Cloneable, Serializable

Implements a set in terms of a hash table. [Sun docs]

See Also:

Serialized Form

Constructor Summary

Constructors

Modifier	Constructor and Description
	HashSet()
	HashSet(Collection<? extends E> c)
protected	HashSet(HashMap<E,Object> map) Protected constructor to specify the underlying map.
	HashSet(int initialCapacity)
	HashSet(int initialCapacity, float loadFactor)

Method Summary

Modifier and Type	Method and Description
boolean	add(E o)
void	clear()
Object	clone()
boolean	contains(Object o)
boolean	isEmpty()
Iterator<E>	iterator()
boolean	remove(Object o)
int	size()

Methods inherited from class java.util.AbstractSet

equals, hashCode, removeAll

Methods inherited from class java.util.AbstractCollection

addAll, containsAll, retainAll, toArray, toArray, toString

Methods inherited from class java.lang.Object

finalize, getClass

Methods inherited from interface java.util.Set

spliterator

Methods inherited from interface java.util.Collection

addAll, containsAll, parallelStream, removeAll, removeIf, retainAll, stream, toArray, toArray

Methods inherited from interface java.lang.Iterable

forEach

Constructor Detail

HashSet

public HashSet()

HashSet

public HashSet(Collection<? extends E> c)

HashSet

public HashSet(int initialCapacity)

HashSet

public HashSet(int initialCapacity,
               float loadFactor)

HashSet

protected HashSet(HashMap<E,Object> map)

Protected constructor to specify the underlying map. This is used by LinkedHashSet.

Parameters:

map - underlying map to use.

Method Detail

add

public boolean add(E o)

Specified by:

add in interface Collection<E>

Overrides:

add in class AbstractCollection<E>

clear

public void clear()

Specified by:

clear in interface Collection<E>

Overrides:

clear in class AbstractCollection<E>

clone

public Object clone()

contains

public boolean contains(Object o)

Specified by:

contains in interface Collection<E>

Overrides:

contains in class AbstractCollection<E>

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface Collection<E>

Overrides:

isEmpty in class AbstractCollection<E>

iterator

public Iterator<E> iterator()

Specified by:

iterator in interface Iterable<E>

remove

public boolean remove(Object o)

Specified by:

remove in interface Collection<E>

Overrides:

remove in class AbstractCollection<E>

size

public int size()

Specified by:

size in interface Collection<E>