org.apache.commons.collections

Interface Predicate

public interface Predicate

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.

Since: Commons Collections 1.0

Version: $Revision: 1.11 $ $Date: 2004/04/14 20:08:57 $

Author: James Strachan Stephen Colebourne

Method Summary
booleanevaluate(Object object)
Use the specified parameter to perform a test that returns true or false.

Method Detail

evaluate

public boolean evaluate(Object object)
Use the specified parameter to perform a test that returns true or false.

Parameters: object the object to evaluate, should not be changed

Returns: true or false

Throws: ClassCastException (runtime) if the input is the wrong class IllegalArgumentException (runtime) if the input is invalid FunctorException (runtime) if the predicate encounters a problem

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