Language

Connection Listener

Frame (Index), No frame                 version:0.3(latest)  

If the mouse is close to the boundary of a shape, then this class calculates a mouse hit point - a point lying on the shape's boundary and close to the mouse - and displays it with the mark or . The mouse hit point is exactly lying on the boundary, and especially the mouse hit point with the mark of is a characteristic point on the shape's boundary (Figure 1, Figure 2).
This class also provides the classes such as Rotate or Translate - which don't implement the MouseListener or MouseMotionListener - with an easy way to calculate and display a mouse hit point, and an easy way to get the exact coordinates of the mouse hit point. The other classes such as CreateShapeLS or MoveResizeShapeLS utilizes the drawMouseHitPT method of this class to connect a connector to a shape at a mouse hit point (connection point).

=> CreateShapeLS: Connector enable option, MoveResizeShapeLS: Figure 2.1, Figure 2.2, Rotate, Translate.

Figure 1. Characteristic points

The characteristic points are endpoints of a line/curve segment, and north, south, east and west points of an ellipse/circle.

Figure 2. The examples of the marks.

Figure_(a) Creating a horizontal line	Figure_(b) The created line is slightly declined.	Figure_(c) A perfect horizontal line

Method	Description
isMouseListener	boolean isMouseListener(MouseListener listener) Inquires whether this object is registered to the ListenerPanel or not.
isMouseMotionListener	public boolean isMouseMotionListener(MouseMotionListener listener) Inquires whether this object is registered to the ListenerPanel or not.
activateListener	private void activateListener(boolean activate) If the activate parameter is true, this method registers this object to the ListenerPanel as a MouseListener and MouseMotionListener. If the activate parameter is false, this method removes this object from the ListenerPanel.
addConnection Listener	public void addConnectionListener(ConnectionListener listener) Adds the specified ConnectionListener object to the listenerList for receiving a ConnectionEvent from the ConnectionLS when shapes are selected in the ConnectionLS.
removeConnection Listener	public void removeConnectionListener(ConnectionListener listener) Remove a ConnectionListener object from the listenerList.
removeConnection Listener	public void removeConnectionListener() Remove all the ConnectionListener object from the listenerList.
fireEvent	public void fireEvent(ConnectionEvent event) Reports a ConnectionEvent to the objects registered in the listenerList when shapes are selected in the ConnectionLS.
mousePressed	public void mousePressed(MouseEvent e) Calls the drawMouseHitPT method and sets its returned value to the mouseHitPoint field. Sets the current mouse position to the startPoint field.
mouseDragged	public void mouseDragged(MouseEvent e) Calls the drawMouseHitPT method and sets its returned value to the mouseHitPoint field. Sets the current mouse position to the endPoint field.
mouseReleased	public void mouseReleased(MouseEvent e) If the mouse is moved unexpectedly and slightly in the mouse click operation, then the following processing will be done and sets true to the clicked field. This method calls the fireEvent method to send the startPoint or the point of the mouseHitPoint to the objects which implement ConnectionListener.
mouseClicked	public void mouseClicked(MouseEvent e) This method calls the fireEvent method to send the startPoint or the point of the mouseHitPoint to the objects which implement ConnectionListener.
mouseEntered	public void mouseEntered(MouseEvent e) Nothing is done.
mouseExited	public void mouseExited(MouseEvent e) Nothing is done.
mouseMoved	public void mouseMoved(MouseEvent e) Nothing is done.
drawMouseHitPT	public CurvePT drawMouseHitPT(int ctrl, Point2D mousePT, Vector2D vec, ShapeContainer movingContainer) Parameters: ctrl - If the mouse is dragged with holding down the Shift/Ctrl/Alt key, then the value of ctrl is 1/2/3 mousePT - The mouse position. vec - The direction in which the mouse hit point is searched. If vec==null, it is searched in any direction around the mousePT. movingContainer - The ShapeContainer objects which are excluded from searching a mouse hit point. Returns: If the mouse hit point is found on a shape's boundary, returns it, otherwise returns null. Processing: Calls the next method with the different parameters.
drawMouseHitPT	private CurvePT drawMouseHitPT(Point2D mousePT, Vector2D vec, double boundaryTol, double pointTol, ShapeContainer movingContainer) Parameters: mousePT - The mouse position. vec - The direction in which the mouse hit point is searched. If vec==null, it is searched in any direction around the mousePT. boundaryTol - The tolerance by which the mousePT is on a boundary of a shape. pointTol - The tolerance by which the mousePT is equal to a characteristic point of a shape. movingContainer - The ShapeContainer objects which are excluded from searching a mouse hit point. : In the case of creating a shape, the shape being created must be excluded, or in the case of moving/resizing shapes, the shapes being moved/resized must be excluded. Returns: If the mouse hit point is found on a shape's boundary, then returns it otherwise returns null. Processing: ∙ Calls the MousePsotionLS.getAllMousePositionInfo method. This is to get the mouse hit testing result (MousePositionInfo objects) and checks whether or not a mouse hit shape exists. ∙ If a hit shape exists, calls the getHitPT method to calculate the mouse hit point accurately. ∙ If a mouse hit point is found, draws the mark (or ) at the mouse hit point by the DrawShapeUtil.drawTempShape method.
getHitPT	private CurvePT getHitPT(Point2D mousePT, Vector2D vec, double boundaryTol, ShapeContainer target) Parameters: mousePT - The mouse position. vec - The direction in which the mouse hit point is searched. If vec==null, it is searched in any direction around the mousePT. boundaryTol - The tolerance by which the mousePT is on a boundary of a shape. target - The ShapeContainer object. A mouse hit point is searched on the boundary of the target. Returns: If the mouse hit point is found on the boundary of the target, returns it, otherwise returns null. Processing: ∙ If the vec isn't null nor 0 vector, then this method tries to find a mouse hit point by the Curve2DUtil.getProjectionLines method. ∙ If the vec is null or 0 vector, then this method tries to find a mouse hit point by the Curve2DUtil.getShortestLine method.
getCloseCharacteristic Point	public double getCloseCharacteristicPoint(ShapeContainer container, double t, double pointTol) Parameters: container - The ShapeContainer object. t - The curve parameter representing the point on the boundary of the container. pointTol - The tolerance by which the mousePT is equal to a characteristic point of a shape. Returns: Return the curve parameter of the characteristic point, if one of the characteristic points of the container is close enough to the point denoted by the t, otherwise return -1.0. Processing: Gets the characteristic points by the Curve2D.getCharacteristicPoints method, and tests if the distance from each of the characteristic points to the point denoted by the t is less than DrawParameters.ConnectionSmallTolerance. If it is less, then returns the curve parameter of the the characteristic point.
drawMark	private void drawMark(Point2D point, int type) Parameters: point - The mark position. type - The mark type (0/1). If type==0, then draws the mark of , otherwise draws the mark of at the point. by the DrawPanelUtil.drawTempShape method.