source: josm/src/org/openstreetmap/josm/actions/mapmode/MapMode.java@ 7

package org.openstreetmap.josm.actions.mapmode;

import java.awt.event.ActionEvent;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;

import javax.swing.AbstractAction;
import javax.swing.ImageIcon;
import javax.swing.JComponent;
import javax.swing.KeyStroke;

import org.openstreetmap.josm.data.osm.DataSet;
import org.openstreetmap.josm.gui.MapFrame;
import org.openstreetmap.josm.gui.MapView;

/**
 * A class implementing MapMode is able to be selected as an mode for map editing.
 * As example scrolling the map is a MapMode, connecting Nodes to new LineSegments
 * is another.
 * 
 * MapModes should register/deregister all necessary listener on the map's view
 * control. 
 */
abstract public class MapMode extends AbstractAction implements MouseListener, MouseMotionListener {

        /**
         * The parent mapframe this mode belongs to.
         */
        protected final MapFrame mapFrame;
        /**
         * Shortcut to the MapView.
         */
        protected final MapView mv;
        /**
         * Shortcut to the DataSet.
         */
        protected final DataSet ds;

        /**
         * Construct a mapMode with the given icon and the given MapFrame
         *
         * @param iconName The filename of the icon.
         * @param mapFrame The parent MapFrame, this MapMode belongs to.
         */
        public MapMode(String name, String iconName, String tooltip, int mnemonic, MapFrame mapFrame) {
                super(name, new ImageIcon("images/mapmode/"+iconName+".png"));
                putValue(MNEMONIC_KEY, mnemonic);
                putValue(ACCELERATOR_KEY, KeyStroke.getKeyStroke(mnemonic,0));
                putValue(LONG_DESCRIPTION, tooltip);
                mapFrame.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW).put(KeyStroke.getKeyStroke(mnemonic,0), this);
                mapFrame.getActionMap().put(this, this);
                this.mapFrame = mapFrame;
                mv = mapFrame.mapView;
                ds = mv.dataSet;
        }
        
        /**
         * Register all listener to the mapView
         * @param mapView       The view, where the listener should be registered.
         */
        public void registerListener() {
                firePropertyChange("active", false, true);
        }
        
        /**
         * Unregister all listener previously registered. 
         * @param mapView       The view from which the listener should be deregistered.
         */
        public void unregisterListener() {
                firePropertyChange("active", true, false);
        }

        /**
         * Call selectMapMode(this) on the parent mapFrame.
         */
        public void actionPerformed(ActionEvent e) {
                mapFrame.selectMapMode(this);
        }
        
        /**
         * Does nothing. Only to subclass.
         */
        public void mouseClicked(MouseEvent e) {}
        /**
         * Does nothing. Only to subclass.
         */
        public void mousePressed(MouseEvent e) {}
        /**
         * Does nothing. Only to subclass.
         */
        public void mouseReleased(MouseEvent e) {}
        /**
         * Does nothing. Only to subclass.
         */
        public void mouseEntered(MouseEvent e) {}
        /**
         * Does nothing. Only to subclass.
         */
        public void mouseExited(MouseEvent e) {}
        /**
         * Does nothing. Only to subclass.
         */
        public void mouseMoved(MouseEvent e) {}
        /**
         * Does nothing. Only to subclass.
         */
        public void mouseDragged(MouseEvent e) {}
}