/* ================================================================

 * Cewolf : Chart enabling Web Objects Framework

 * ================================================================

 *

 * Project Info:  http://cewolf.sourceforge.net

 * Project Lead:  Guido Laures (guido@laures.de);

 *

 * (C) Copyright 2002, by Guido Laures

 *

 * This library is free software; you can redistribute it and/or modify it under the terms

 * of the GNU Lesser General Public License as published by the Free Software Foundation;

 * either version 2.1 of the License, or (at your option) any later version.

 *

 * This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;

 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

 * See the GNU Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public License along with this

 * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,

 * Boston, MA 02111-1307, USA.

 */

package de.laures.cewolf;

import java.util.Map;

/**

 * Postprocesses a generated chart instance. Objects of this class can be used to

 * customize a generated and afterwards rendered chart instance additionally.

 * To provide a postprocessor the <chartpostprocessor> tag is used. 

 * There can be an unlimited number of postprocessors registered.

 * @see de.laures.cewolf.taglib.tags.ChartPostProcessorTag

 * @author  Guido Laures

 */

public interface ChartPostProcessor {

    /**

     * Processes a generated chart. This method is called by the ChartProducer

     * after a chart instance is generated and before it is rendered (if so).

     * The ChartProducer is responsible for post processing a chart dependant

     * on and only on the provided parameters. This means that the same parameters

     * should result in the same post processings.

     * @param chart the chart instnce. Concrete class depends on the rendering

     * implementation. Currently a org.jfree.chart.JFreeChart is passed.

     * @param params paramters passed to the postprocessor. These are defined in the JSP

     * @see de.laures.cewolf.taglib.tags.ChartPostProcessorTag

     */

    void processChart(Object chart, Map params);

}