org.pcollections
Class MapPBag<E>

java.lang.Object
  java.util.AbstractCollection<E>
      org.pcollections.MapPBag<E>

Type Parameters:

E -

All Implemented Interfaces:

Iterable<E>, Collection<E>, PBag<E>, PCollection<E>

public final class MapPBag<E>
extends AbstractCollection<E>
implements PBag<E>

A map-backed persistent bag.

If the backing map is thread-safe, then this implementation is thread-safe (assuming Java's AbstractCollection is thread-safe), although its iterators may not be.

Author:

harold

Method Summary

boolean	contains(Object e)
static <E> MapPBag<E>	empty(PMap<E,Integer> map)
boolean	equals(Object that)
int	hashCode()
Iterator<E>	iterator()
MapPBag<E>	minus(Object e)
MapPBag<E>	minusAll(Collection<?> list)
MapPBag<E>	plus(E e)
MapPBag<E>	plusAll(Collection<? extends E> list)
int	size()

Methods inherited from class java.util.AbstractCollection

add, addAll, clear, containsAll, isEmpty, remove, removeAll, retainAll, toArray, toArray, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.pcollections.PCollection

add, addAll, clear, remove, removeAll, retainAll

Methods inherited from interface java.util.Collection

containsAll, isEmpty, toArray, toArray

Method Detail

empty

public static <E> MapPBag<E> empty(PMap<E,Integer> map)

Type Parameters:

E -

Parameters:

map -

Returns:

a PBag backed by an empty version of map, i.e. by map.minusAll(map.keySet())

size

public int size()

Specified by:

size in interface Collection<E>

Specified by:

size in class AbstractCollection<E>

iterator

public Iterator<E> iterator()

Specified by:

iterator in interface Iterable<E>

Specified by:

iterator in interface Collection<E>

Specified by:

iterator in class AbstractCollection<E>

contains

public boolean contains(Object e)

Specified by:

contains in interface Collection<E>

Overrides:

contains in class AbstractCollection<E>

hashCode

public int hashCode()

Specified by:

hashCode in interface Collection<E>

Overrides:

hashCode in class Object

equals

public boolean equals(Object that)

Specified by:

equals in interface Collection<E>

Overrides:

equals in class Object

plus

public MapPBag<E> plus(E e)

Specified by:

plus in interface PBag<E>

Specified by:

plus in interface PCollection<E>

Parameters:

e - non-null

Returns:

a collection which contains e and all of the elements of this

minus

public MapPBag<E> minus(Object e)

Specified by:

minus in interface PBag<E>

Specified by:

minus in interface PCollection<E>

Returns:

this with a single instance of e removed, if e is in this

plusAll

public MapPBag<E> plusAll(Collection<? extends E> list)

Specified by:

plusAll in interface PBag<E>

Specified by:

plusAll in interface PCollection<E>

Parameters:

list - contains no null elements

Returns:

a collection which contains all of the elements of list and this

minusAll

public MapPBag<E> minusAll(Collection<?> list)

Specified by:

minusAll in interface PBag<E>

Specified by:

minusAll in interface PCollection<E>

Returns:

this with all elements of list completely removed