org.joda.util
Class IdentityBasedHashSet

java.lang.Object
  |
  +--java.util.AbstractCollection
        |
        +--java.util.AbstractSet
              |
              +--org.joda.util.IdentityBasedHashSet

All Implemented Interfaces:

java.lang.Cloneable, java.util.Collection, java.io.Serializable, java.util.Set

public class IdentityBasedHashSet

extends java.util.AbstractSet

implements java.lang.Cloneable, java.io.Serializable

Set based on Hash principles which check for equality, not equals. This is probably not terribly efficient!

Author:

Stephen Colebourne

See Also:

Serialized Form

Nested Class Summary

static class

IdentityBasedHashSet.Entry Hash entry.

Constructor Summary

IdentityBasedHashSet()
Constructs a new, empty set with a default capacity and load factor, which is 0.75.

IdentityBasedHashSet(java.util.Collection coll)
Constructs a new set with the same mappings as the given map.

IdentityBasedHashSet(int initialCapacity)
Constructs a new, empty map with the specified initial capacity and default load factor, which is 0.75.

IdentityBasedHashSet(int initialCapacity, float loadFactor)
Constructs a new, empty set with the specified initial capacity and the specified load factor.

Method Summary

boolean	add(java.lang.Object obj) Adds the specified value to the set.
void	clear() Removes all values from this set.
java.lang.Object	clone() Returns a shallow copy of this set instance: the values themselves are not cloned.
boolean	contains(java.lang.Object obj) Returns true if this set contains the object.
boolean	isEmpty() Returns true if the size is 0.
java.util.Iterator	iterator() Get an iterator accross the set
boolean	remove(java.lang.Object key) Removes the mapping for this key from this map if present.
int	size() Returns the size of the set.

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, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Set

addAll, containsAll, retainAll, toArray, toArray

Constructor Detail

IdentityBasedHashSet

public IdentityBasedHashSet(int initialCapacity,
                            float loadFactor)

Constructs a new, empty set with the specified initial capacity and the specified load factor.

Parameters:

initialCapacity - the initial capacity of the set.

loadFactor - the load factor of the set

Throws:

java.lang.IllegalArgumentException - if the initial capacity is less than zero, or if the load factor is nonpositive.

IdentityBasedHashSet

public IdentityBasedHashSet(int initialCapacity)

Constructs a new, empty map with the specified initial capacity and default load factor, which is 0.75.

Parameters:

initialCapacity - the initial capacity of the HashMap.

Throws:

java.lang.IllegalArgumentException - if the initial capacity is less than zero.

IdentityBasedHashSet

public IdentityBasedHashSet()

Constructs a new, empty set with a default capacity and load factor, which is 0.75.

IdentityBasedHashSet

public IdentityBasedHashSet(java.util.Collection coll)

Constructs a new set with the same mappings as the given map. The map is created with a capacity of twice the number of mappings in the given map or 11 (whichever is greater), and a default load factor, which is 0.75.

Method Detail

size

public int size()

Returns the size of the set.

Specified by:

size in interface java.util.Set

Specified by:

size in class java.util.AbstractCollection

Returns:

size

isEmpty

public boolean isEmpty()

Returns true if the size is 0.

Specified by:

isEmpty in interface java.util.Set

Overrides:

isEmpty in class java.util.AbstractCollection

Returns:

true if empty

contains

public boolean contains(java.lang.Object obj)

Returns true if this set contains the object.

Specified by:

contains in interface java.util.Set

Overrides:

contains in class java.util.AbstractCollection

Parameters:

obj - the object to check for

Returns:

true if Set contains object by identity

add

public boolean add(java.lang.Object obj)

Adds the specified value to the set.

Specified by:

add in interface java.util.Set

Overrides:

add in class java.util.AbstractCollection

Parameters:

obj - object to add

Returns:

true if object added

remove

public boolean remove(java.lang.Object key)

Removes the mapping for this key from this map if present.

Specified by:

remove in interface java.util.Set

Overrides:

remove in class java.util.AbstractCollection

Parameters:

key - key whose mapping is to be removed from the map.

Returns:

previous value associated with specified key, or null if there was no mapping for key. A null return can also indicate that the map previously associated null with the specified key.

clear

public void clear()

Removes all values from this set.

Specified by:

clear in interface java.util.Set

Overrides:

clear in class java.util.AbstractCollection

clone

public java.lang.Object clone()

Returns a shallow copy of this set instance: the values themselves are not cloned.

Overrides:

clone in class java.lang.Object

Returns:

a shallow copy of this map.

iterator

public java.util.Iterator iterator()

Get an iterator accross the set

Specified by:

iterator in interface java.util.Set

Specified by:

iterator in class java.util.AbstractCollection