001/**
002 * Copyright 2005-2016 The Kuali Foundation
003 *
004 * Licensed under the Educational Community License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.opensource.org/licenses/ecl2.php
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016package org.kuali.rice.krad.datadictionary.validation.constraint;
017
018import java.io.Serializable;
019
020
021/**
022 * This is the marker interface for constraints. Constraints are a central concept in the Rice data dictionary validation, and are the
023 * primary mechanism by which the validation of an object or one of its attributes takes place. For example, by imposing a length constraint
024 * on an attribute of a business object, it's possible to indicate that only values shorter (or longer) than a specific number of characters
025 * are valid for that attribute. 
026 * 
027 * Any interface that extends Constraint is by definition a constraint, and may have one of the following defined:
028 * 
029 * - A sub-interface for {@see Constrainable} that advises on how a constraint maps to data dictionary metadata
030 * - A {@see ConstraintProvider} that looks up constraints for a specific constrainable definition
031 * - A {@see ConstraintProcessor} that processes the constraint against some object value to determine if it is valid
032 * 
033 * @author Kuali Rice Team (rice.collab@kuali.org) 
034 * @since 1.1
035 */
036public interface Constraint extends Serializable {
037        
038        // Empty - since this is a marker interface, all of the interesting stuff is in interfaces or classes that extend this interface
039        
040}