/*
* @(#)AbstractConnector.java
*
* Project: JHotdraw - a GUI framework for technical drawings
* http://www.jhotdraw.org
* http://jhotdraw.sourceforge.net
* Copyright: (c) by the original author(s) and all contributors
* License: Lesser GNU Public License (LGPL)
* http://www.opensource.org/licenses/lgpl-license.html
*/
package org.jhotdraw.standard;
import java.awt.*;
import java.io.IOException;
import org.jhotdraw.framework.*;
import org.jhotdraw.util.*;
/**
* AbstractConnector provides default implementation for
* the Connector interface.
*
* @see Connector
*
* @version <$CURRENT_VERSION$>
*/
public abstract class AbstractConnector implements Connector {
/**
* the owner of the connector
*/
protected Figure fOwner;
/*
* Serialization support.
*/
private static final long serialVersionUID = -5170007865562687545L;
private int abstractConnectorSerializedDataVersion = 1;
/**
* Constructs a connector that has no owner. It is only
* used internally to resurrect a connectors from a
* StorableOutput. It should never be called directly.
*/
public AbstractConnector() {
fOwner = null;
}
/**
* Constructs a connector with the given owner figure.
*/
public AbstractConnector(Figure owner) {
fOwner = owner;
}
/**
* Gets the connector's owner.
* Which is the figure this is attached too and NOT the connection it may be
* attached too.
*
*/
public Figure owner() {
return fOwner;
}
public Point findStart(ConnectionFigure connection) {
return findPoint(connection);
}
public Point findEnd(ConnectionFigure connection) {
return findPoint(connection);
}
/**
* Gets the connection point. Override when the connector
* does not need to distinguish between the start and end
* point of a connection.
*/
protected Point findPoint(ConnectionFigure connection) {
return Geom.center(displayBox());
}
/**
* Gets the display box of the connector.
*/
public Rectangle displayBox() {
return owner().displayBox();
}
/**
* Tests if a point is contained in the connector.
*/
public boolean containsPoint(int x, int y) {
return owner().containsPoint(x, y);
}
/**
* Draws this connector. By default connectors are invisible.
*/
public void draw(Graphics g) {
// invisible by default
}
/**
* Stores the connector and its owner to a StorableOutput.
*/
public void write(StorableOutput dw) {
dw.writeStorable(owner());
}
/**
* Reads the connector and its owner from a StorableInput.
*/
public void read(StorableInput dr) throws IOException {
try {fOwner = (Figure)dr.readStorable();}
catch (ClassCastException ex) {
Object o = dr.readStorable();
System.out.println("Class Cast Exception " + o.toString());
}
}
/**
* Requests that the connector should show itself or hide itself. The
* ConnectionFigure which desires to connect to this Connector is passed in.
* It a connector should show itself it should do so when draw is called, if
* so desired.
*/
public void connectorVisibility(boolean isVisible, ConnectionFigure courtingConnection) {
//invisible by default
}
/**
* SupportsConnector dragging.
*
*/
public Point connectorMovedTo(int x, int y){
return new Point(x,y);
}
/**
* Returns a 'finalized' connector. Can be used to change Connector.
*
* @param start - true if a startConnector
* @return - final Connector
*/
public Connector finalizeConnector(boolean start){
return this;
}
}