org.zedlib
Interface Bag

All Superinterfaces:

Collection, Function, Relation, Set, Set

All Known Implementing Classes:

HashBag

public interface Bag

extends Function

Bags are collections of elements of X in which the number of times an element occurs is significant.

Author:

Brad Long

Method Summary

boolean	add(Baglet b) Adds a maplet to this relation.
boolean	add(Object x, int y) Adds an object to this bag with the specified number of occurrences.
boolean	containsMember(Object x) Determines whether an object is in the bag.
boolean	containsValue(int count) A convenience function for the alternative range().contains(new Integer(count)).
int	getCount(Object o) Counts the number of times an element appears in this bag.
boolean	isSubBagOf(Bag c) Determines whether this bag is a sub-bag of a given bag.
Object	put(Object x, int y) Adds an object to this bag a specified number of times.

Methods inherited from interface org.zedlib.Function

containsKey, containsValue, getMaplet, put

Methods inherited from interface org.zedlib.Relation

add, add, addAll, composition, domain, domainAntiRestriction, domainRestriction, image, inverse, isFunction, isInjection, isReflexive, override, range, rangeAntiRestriction, rangeRestriction, transitiveClosure

Methods inherited from interface org.zedlib.Set

cartesianProduct, difference, identity, intersection, isSubsetOf, isSupersetOf, union

Methods inherited from interface java.util.Set

add, addAll, clear, contains, containsAll, equals, hashCode, isEmpty, iterator, remove, removeAll, retainAll, size, toArray, toArray

Method Detail

getCount

public int getCount(Object o)

Counts the number of times an element appears in this bag.

Parameters:

o - the object for which to count occurrences

Returns:

the number of times the given key appears in the bag

containsValue

public boolean containsValue(int count)

A convenience function for the alternative range().contains(new Integer(count)).

Parameters:

count - any integer

Returns:

true if at least one object exists in the bag occurrence times.

add

public boolean add(Object x,
                   int y)

Adds an object to this bag with the specified number of occurrences.

Parameters:

x - the object to add

y - the number of times the object should appear in the bag

Returns:

true if the maplet was added or false if the maplet already exists or number of occurrences given is less then one.

add

public boolean add(Baglet b)

Adds a maplet to this relation.

Parameters:

b - the baglet to add to this bag

Returns:

true if the given maplet was added to this relation

See Also:

Set.add(Object o)

put

public Object put(Object x,
                  int y)

Adds an object to this bag a specified number of times.

Parameters:

x - the object to add

y - the number of times the object should appear in the bag

Returns:

the Integer object that was replaced or null if x was not previously in the bag.

containsMember

public boolean containsMember(Object x)

Determines whether an object is in the bag. The relationship B.containsMember(x) holds exactly if x appears in B a non-zero number of times. A convenience function for the alternative domain().contains(x).

Parameters:

x - the object to check for existence

Returns:

true if the object is in the bag

isSubBagOf

public boolean isSubBagOf(Bag c)

Determines whether this bag is a sub-bag of a given bag. A bag B is a sub-bag of another bag C if each element occurs in B no more often than it occurs in C.

Parameters:

c - any bag

Returns:

true if this bag is a sub-bag of c