001// Copyright 2004, 2005 The Apache Software Foundation
002//
003// Licensed under the Apache License, Version 2.0 (the "License");
004// you may not use this file except in compliance with the License.
005// You may obtain a copy of the License at
006//
007//     http://www.apache.org/licenses/LICENSE-2.0
008//
009// Unless required by applicable law or agreed to in writing, software
010// distributed under the License is distributed on an "AS IS" BASIS,
011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012// See the License for the specific language governing permissions and
013// limitations under the License.
014
015package org.apache.tapestry.contrib.table.model;
016
017/**
018 * An interface for converting an object to its primary key and back. 
019 * Typically used to determine how to store a given object as a hidden 
020 * value when rendering a form.
021 * 
022 * @author mb
023 * @since 3.0
024 */
025public interface IPrimaryKeyConvertor
026{
027    /**
028     * Gets the serializable primary key of the given value
029     * 
030     * @param objValue the value for which a primary key needs to be extracted
031     * @return the serializable primary key of the value
032     */
033    Object getPrimaryKey(Object objValue);
034    
035    /**
036     * Gets the value corresponding the given primary key 
037     *  
038     * @param objPrimaryKey the primary key for which a value needs to be generated
039     * @return the generated value corresponding to the given primary key
040     */
041    Object getValue(Object objPrimaryKey); 
042}