RequestFilter.java

/**
 * This program 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 3 of the License, or
 * (at your option) any later version.
 *
 *  This program 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 General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 * 
 * @author Arne Kepp, OpenGeo, Copyright 2009
 */
package org.geowebcache.filter.request;

import java.io.Serializable;

import org.geowebcache.GeoWebCacheException;
import org.geowebcache.conveyor.ConveyorTile;
import org.geowebcache.layer.TileLayer;

/** 
 * This is just a dummy class. Should be abstract, 
 * but that gets tricky with XStream
 */
public abstract class RequestFilter implements Serializable {

    private static final long serialVersionUID = -1058186522442111377L;
    
    private String name;
    
    /**
     * Apply the filter to the 
     * 
     * @param convTile
     * @throws RequestFilterException
     */
    public abstract void apply(ConveyorTile convTile) throws RequestFilterException;
    
    /**
     * The name of the filter, as chosen by the user. It should be unique, but this is not enforced.
     * @return
     */
    public String getName() { 
        return name;
    }
    
    
    /**
     * @param name the name to set
     */
    void setName(String name) {
        this.name = name;
    }

    /**
     * Optional initialization 
     */
    public abstract void initialize(TileLayer layer) throws GeoWebCacheException;

    /**
     * Optional updates, filters should implement at least one. The first two are used for
     * filters that can update themselves (eg. WMSRasterFilter), the last one for those that need input.
     */
    
    public abstract boolean update(TileLayer layer, String gridSetId);

    public abstract void update(TileLayer layer, String gridSetId, int zoomStart, int zoomStop) throws GeoWebCacheException;

    public abstract void update(byte[] filterData, TileLayer layer, String gridSetId, int z) throws GeoWebCacheException;
}