/**
 *
 *  Copyright 2005 The Apache Software Foundation or its licensors, as applicable.
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */
package org.apache.tuscany.das.rdb;

/**
 * A lightweight Tabele-column <--> DataObject-property converter framework.
 * Converters allow a user to insert a transformation between a column value and
 * is destination DataObject property value. For example, by default, a VARCHAR
 * column will be represented as a String in its corresponding DataObject
 * property. A user could insert a converter that transforms the the VARCHAR
 * value to an Integer. If this is done then although the column returns
 * character data, the DataObject property will be an Integer
 * 
 * 
 */
public interface Converter {

	/**
	 * Transform the columnData object to a new value and possibly new type.
	 * This should be the invers operation of #getColumnValue
	 * 
	 * @param columnData
	 *            The column value to transorm
	 * @return Returns the transformed value
	 */
	public Object getPropertyValue(Object columnData);

	/**
	 * Transform the columnData object to a new value and possibly new type.
	 * This should be the invers operation of #getPropertyValue
	 * 
	 * @param propertyData
	 *            The property value to transform
	 * @return Returns the transformed value
	 */
	public Object getColumnValue(Object propertyData);

}