org.apache.commons.collections.Predicate Maven / Gradle / Ivy
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* (the "License"); you may not use this file except in compliance with
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*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
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*/
package org.apache.commons.collections;
/**
* 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: 646777 $ $Date: 2008-04-10 14:33:15 +0200 (Thu, 10 Apr 2008) $
*
* @author James Strachan
* @author Stephen Colebourne
*/
public interface Predicate {
/**
* Use the specified parameter to perform a test that returns true or false.
*
* @param object the object to evaluate, should not be changed
* @return true or false
* @throws ClassCastException (runtime) if the input is the wrong class
* @throws IllegalArgumentException (runtime) if the input is invalid
* @throws FunctorException (runtime) if the predicate encounters a problem
*/
public boolean evaluate(Object object);
}