/*
* @(#)LineConnection.java
*
* Project: JHotdraw - a GUI framework for technical drawings
* http://www.jhotdraw.org
* http://jhotdraw.sourceforge.net
* Copyright: ?by the original author(s) and all contributors
* License: Lesser GNU Public License (LGPL)
* http://www.opensource.org/licenses/lgpl-license.html
*/
package research.connection;
import research.figure.PolyLineFigure;
import research.figure.ArrowTip;
import research.*;
import research.connector.Connector;
import research.store.StorableOutput;
import research.store.StorableInput;
import java.awt.*;
import java.util.*;
import java.io.*;
/**
* A LineConnection is a standard implementation of the
* ConnectionFigure interface. The interface is implemented with PolyLineFigure.
*
* @see research.ConnectionFigure
*
* @version <$CURRENT_VERSION$>
*/
public class LineConnection extends PolyLineFigure implements ConnectionFigure {
protected Connector myStartConnector;
protected Connector myEndConnector;
/*
* Serialization support.
*/
private static final long serialVersionUID = 6883731614578414801L;
private int lineConnectionSerializedDataVersion = 1;
/**
* Constructs a LineConnection. A connection figure has
* an arrow decoration at the start and end.
*/
public LineConnection() {
super(4);
this.setAttribute("connectability", Boolean.valueOf(false));
}
/**
* Ensures that a connection is updated if the connection
* was moved.
*/
@Override
protected void basicMoveBy(int dx, int dy) {
// don't move the start and end point since they are connected
for (int i = 1; i < fPoints.size() - 1; i++) {
((Point) fPoints.elementAt(i)).translate(dx, dy);
}
//updateConnection(); // make sure that we are still connected
layoutConnection();
}
/**
* Sets the start figure of the connection.
*/
public void connectStart(Connector newStartConnector) {
setStartConnector(newStartConnector);
startFigure().addFigureChangeListener(this);
}
/**
* Sets the end figure of the connection.
*/
public void connectEnd(Connector newEndConnector) {
setEndConnector(newEndConnector);
endFigure().addFigureChangeListener(this);
handleConnect(startFigure(), endFigure());
}
/**
* Disconnects the start figure.
*/
public void disconnectStart() {
startFigure().removeFigureChangeListener(this);
setStartConnector(null);
}
/**
* Disconnects the end figure.
*/
public void disconnectEnd() {
handleDisconnect(startFigure(), endFigure());
endFigure().removeFigureChangeListener(this);
setEndConnector(null);
}
/**
* Tests whether a connection connects the same figures
* as another ConnectionFigure.
*/
public boolean connectsSame(ConnectionFigure other) {
return other.getStartConnector() == getStartConnector() && other.getEndConnector() == getEndConnector();
}
/**
* Handles the disconnection of a connection.
* Override this method to handle this event.
*/
protected void handleDisconnect(Figure start, Figure end) {
}
/**
* Handles the connection of a connection.
* Override this method to handle this event.
*/
protected void handleConnect(Figure start, Figure end) {
}
/**
* Gets the start figure of the connection.
*/
public Figure startFigure() {
if (getStartConnector() != null) {
return getStartConnector().owner();
}
return null;
}
/**
* Gets the end figure of the connection.
*/
public Figure endFigure() {
if (getEndConnector() != null) {
return getEndConnector().owner();
}
return null;
}
protected void setStartConnector(Connector newStartConnector) {
myStartConnector = newStartConnector;
}
/**
* Gets the start figure of the connection.
*/
public Connector getStartConnector() {
return myStartConnector;
}
protected void setEndConnector(Connector newEndConnector) {
myEndConnector = newEndConnector;
}
/**
* Gets the end figure of the connection.
*/
public Connector getEndConnector() {
return myEndConnector;
}
/**
* Tests whether two figures can be connected.
*/
public boolean canConnect(Figure start, Figure end) {
return true;
}
/**
* Sets the start point.
*/
public void startPoint(int x, int y) {
willChange();
_startPoint(x, y);
changed();
}
protected void _startPoint(int x, int y) {
Point start = new Point(x, y);
if (fPoints.size() == 0) {
fPoints.addElement(start);
} else {
fPoints.setElementAt(start, 0);
}
}
/**
* Sets the end point.
*/
public void endPoint(int x, int y) {
willChange();
_endPoint(x, y);
changed();
}
protected void _endPoint(int x, int y) {
if (fPoints.size() < 2) {
fPoints.addElement(new Point(x, y));
} else {
fPoints.setElementAt(new Point(x, y), fPoints.size() - 1);
}
}
/**
* Gets the start point.
*/
public Point startPoint() {
Point p = (Point) fPoints.firstElement();
return new Point(p.x, p.y);
}
/**
* Gets the end point.
*/
public Point endPoint() {
Point p = (Point) fPoints.lastElement();
return new Point(p.x, p.y);
}
/**
* Gets the handles of the figure. It returns the normal
* PolyLineHandles but adds ChangeConnectionHandles at the
* start and end.
*/
@Override
public Vector handles() {
Vector handles = new Vector(fPoints.size());
handles.addElement(new ChangeConnectionStartHandle(this));
for (int i = 1; i < fPoints.size() - 1; i++) {
handles.addElement(new PolyLineHandle(this, locator(i), i));
}
handles.addElement(new ChangeConnectionEndHandle(this));
return handles;
}
/**
* Sets the point and updates the connection.
*/
@Override
public void setPointAt(Point p, int i) {
super.setPointAt(p, i);
//layoutConnection();
}
/**
* Inserts the point and updates the connection.
*/
@Override
public void insertPointAt(Point p, int i) {
super.insertPointAt(p, i);
//layoutConnection();
}
/**
* Removes the point and updates the connection.
*/
@Override
public void removePointAt(int i) {
super.removePointAt(i);
//layoutConnection();
}
/**
* Updates the connection.
*/
public void updateConnection() {
willChange();
_updateConnection();
changed();
}
protected void _updateConnection() {
if (getStartConnector() != null) {
Point start = getStartConnector().findStart(this);
if (start != null) {
_startPoint(start.x, start.y);
}
}
if (getEndConnector() != null) {
Point end = getEndConnector().findEnd(this);
if (end != null) {
_endPoint(end.x, end.y);
}
}
}
/**
* Lays out the connection. This is called when the connection
* itself changes. By default the connection is recalculated
*/
public void layoutConnection() {
willChange();
_layoutConnection();
changed();
}
protected void _layoutConnection() {
_updateConnection();
}
public void figureChanged(FigureChangeEvent e) {
//updateConnection();
layoutConnection();
}
public void figureRemoved(FigureChangeEvent e) {
if (listener() != null) {
listener().figureRequestRemove(new FigureChangeEvent(this));
}
}
public void figureRequestRemove(FigureChangeEvent e) {
}
public void figureInvalidated(FigureChangeEvent e) {
}
public void figureRequestUpdate(FigureChangeEvent e) {
}
@Override
public void release() {
super.release();
handleDisconnect(startFigure(), endFigure());
if (getStartConnector() != null) {
startFigure().removeFigureChangeListener(this);
}
if (getEndConnector() != null) {
endFigure().removeFigureChangeListener(this);
}
}
public void write(StorableOutput dw) {
super.write(dw);
dw.writeStorable(getStartConnector());
dw.writeStorable(getEndConnector());
}
public void read(StorableInput dr) throws IOException {
super.read(dr);
Connector start = (Connector) dr.readStorable();
if (start != null) {
connectStart(start);
}
Connector end = (Connector) dr.readStorable();
if (end != null) {
connectEnd(end);
}
if (start != null && end != null) {
//updateConnection();
layoutConnection();
}
}
private void readObject(ObjectInputStream s)
throws ClassNotFoundException, IOException {
s.defaultReadObject();
if (getStartConnector() != null) {
connectStart(getStartConnector());
}
if (getEndConnector() != null) {
connectEnd(getEndConnector());
}
}
}