org.apache.commons.collections4.functors
Interface Equator<T>

Type Parameters:

T - the types of object this Equator can evaluate.

All Known Implementing Classes:

DefaultEquator

public interface Equator<T>

An equation function, which determines equality between objects of type T.

It is the functional sibling of Comparator; Equator is to Object as Comparator is to Comparable.

Since:

4.0

Version:

$Id: Equator.java 1477798 2013-04-30 19:49:02Z tn $

equate

boolean equate(T o1,
               T o2)

Evaluates the two arguments for their equality.

Parameters:

o1 - the first object to be equated.

o2 - the second object to be equated.

Returns:

whether the two objects are equal.

hash

int hash(T o)

Calculates the hash for the object, based on the method of equality used in the equate method. This is used for classes that delegate their equals(Object) method to an Equator (and so must also delegate their hashCode() method), or for implementations of HashedMap that use an Equator for the key objects.

Parameters:

o - the object to calculate the hash for.

Returns:

the hash of the object.