Defines a functor interface implemented by classes that perform a predicate test on an object.
A
Predicate
is the object equivalent of an
if
statement. It uses the input object to return a true or false value, and is often used in validation or filtering.
Standard implementations of common predicates are provided by {@link PredicateUtils}. These include true, false, instanceof, equals, and, or, not, method invokation and null testing.
@author James Strachan
@author Matt Hall, John Watkinson, Stephen Colebourne
@version $Revision: 1.1 $ $Date: 2005/10/11 17:05:19 $
@since Commons Collections 1.0