broadwick.math

Class SetOperations

java.lang.Object

broadwick.math.SetOperations

public final class SetOperations
extends Object

Some basic set operations on the Java Set class.

Constructor Summary

Constructors

Modifier	Constructor and Description
private	SetOperations() Hidden utility constructor.

Method Summary

Modifier and Type	Method and Description
static <T> Set<T>	difference(Set<T> setA, Set<T> setB) Get the set difference A\B of the sets A and B.
static <T> Set<T>	intersection(Collection<T> setA, Collection<T> setB) Get the intersection of two sets.
static <T> boolean	isSubset(Set<T> setA, Set<T> setB) Is setA a subset of setB.
static <T> boolean	isSuperset(Set<T> setA, Set<T> setB) Is setA a superset of setB.
static <T> Set<T>	symDifference(Set<T> setA, Set<T> setB) Get the elements of sets A,B that are not in their intersection.
static <T> Set<T>	union(Set<T> setA, Set<T> setB) Get the union of two sets.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SetOperations

private SetOperations()

Hidden utility constructor.

Method Detail

union

public static <T> Set<T> union(Set<T> setA,
                               Set<T> setB)

Get the union of two sets.

Type Parameters:

T - The genetic type of the sets used.

Parameters:

setA - one of two sets for the union

setB - second of two sets for the union

Returns:

setA union setB

intersection

public static <T> Set<T> intersection(Collection<T> setA,
                                      Collection<T> setB)

Get the intersection of two sets.

Type Parameters:

T - The generic type of the sets used.

Parameters:

setA - one of two sets for the intersection

setB - second of two sets for the intersection

Returns:

setA intersection setB

difference

public static <T> Set<T> difference(Set<T> setA,
                                    Set<T> setB)

Get the set difference A\B of the sets A and B.

Type Parameters:

T - The genetic type of the sets used.

Parameters:

setA - the set whose elements will be retained.

setB - the set whose elements will be subtracted from A.

Returns:

setA minus setB

symDifference

public static <T> Set<T> symDifference(Set<T> setA,
                                       Set<T> setB)

Get the elements of sets A,B that are not in their intersection.

Type Parameters:

T - The generic type of the sets used.

Parameters:

setA - one of two sets for the intersection

setB - second of two sets for the intersection

Returns:

(setA union setB) minus (setA union setB)

isSubset

public static <T> boolean isSubset(Set<T> setA,
                                   Set<T> setB)

Is setA a subset of setB.

Type Parameters:

T - The generic type of the sets used.

Parameters:

setA - the (potential) subset.

setB - the original (superset).

Returns:

true if setA is a subset of setB.

isSuperset

public static <T> boolean isSuperset(Set<T> setA,
                                     Set<T> setB)

Is setA a superset of setB.

Type Parameters:

T - The generic type of the sets used.

Parameters:

setA - the (potential) superset.

setB - setB the original set.

Returns:

true if setA is a superset of setB