public CellListCanvas(BaseGUIAgentImpl uiAgent) 
{
                   // The color of a cell that isn't being monitored, but that we know about.
	super();
	setSize(100, 300);
	monitoredCells = new Vector();
	orderedCells = new Vector();
	cellColors = new Hashtable();
	cellInfo = new Hashtable();
	cellRects = new Hashtable();
	shortNames = new Hashtable();
	unmonitoredCellColor = Color.gray;
	this.uiAgent = uiAgent;
	(new Thread( new Runnable() {
	    public void run() {
		while( true ) {
		    try {
			Thread.sleep( 1000 );
		    } catch( InterruptedException error ) { }
		    render();
		}
	    }
	})).start();
	addMouseListener(this);
	setVisible(true);
}

 public Color addMonitoredCell(CellAddress cell) 
{
	Color col = null;
	// if a new cell, create a new random color, pastelize it and use it
	col = (Color)cellColors.get(cell);
	if (col == null) {
	    col = createNewColor();
	    col = makePastel( col );
	    cellColors.put( cell, col );
	}
	if (!monitoredCells.contains(cell))
	    monitoredCells.addElement(cell);
	if (cellRects.get(cell) == null)
	    cellRects.put( cell, new Rectangle(rectSize) );
	rearrangeOrdered();
	render(super.getGraphics());
	return (col);
}

Create a color that the UI will use to distinguish this cell from the others.

 public  void addUnmonitoredCell(CellAddress cell) 
{
	cellRects.put( cell, new Rectangle(rectSize) );
}

 public Color getColor(CellAddress cell) 
{
 return ((Color)cellColors.get(cell));
}

Get the color of cell's border.

 public BaseGUIAgentImpl getUI() 
{
 return (uiAgent);
}

 public  void mouseClicked(MouseEvent event) 
{

}

 public  void mouseDragged(MouseEvent event) 
{

}

 public  void mouseEntered(MouseEvent event) 
{

}

 public  void mouseExited(MouseEvent event) 
{

}

 public  void mouseMoved(MouseEvent event) 
{

}

 public  void mousePressed(MouseEvent event) 
{
	
	// Figure out which mouse button it was from the meta/alt flags.
	int mouseButton = -1;
	selectedCell = null;
	if (event.isAltDown()) {
	    mouseButton = 1;
	} else if (event.isMetaDown()) {
	    mouseButton = 2;
	} else {
	    mouseButton = 0;
	}
	// Figure out which icon was pressed.
	Enumeration e = orderedCells.elements();
	while (e.hasMoreElements()) {
	    CellAddress tCell = (CellAddress)e.nextElement();
	    if ( ((Rectangle)cellRects.get(tCell)).contains(event.getX(), event.getY()) ) {
		selectedCell = tCell;
		break;
	    }
	}
	if ( selectedCell == null ) {  	    // Whoops, mouse missed.
	    Debug.notice("There's nothing at (" + event.getX() + ", " + event.getY() + ")");
	    return;
	} else if ( selectedCell != null ) {
	    if (mouseButton == 0) {
	    } else if (mouseButton == 2) {           // Handle Popup menu stuff.
		String cellName = selectedCell.toString();
		PopupMenu pm = new PopupMenu( cellName );
		if( Global.windowsOS == true ) {     // hack stupid Windows JDK bug in popups
		    pm.add(cellName);
		    pm.add("-");
		}
		for (int i = 0; i <  uiAgent.defaultCellCmds.length; i++)
		    pm.add(uiAgent.defaultCellCmds[i]);
		pm.addActionListener( new ActionListener() { 
		    public void actionPerformed(ActionEvent ae) {
			String command = ae.getActionCommand();/*
			    if (monitoredCells.contains(selectedCell)) {
				addUnmonitoredCell(selectedCell);    // Not being monitored, but still not gone.
				rearrangeOrdered();
			    }
			    //else addMonitoredCell(selectedCell);
			    //rearrangeOrdered();
			} else if (command.equals(BaseUIAgentImpl.changeShowCellAgentsCmd)) {
			} else if (command.equals(BaseUIAgentImpl.killCellCmd)) {
			}
							       */
			uiAgent.invokeCellMenuCommand(selectedCell, command);
			if (command.equals(BaseUIAgentImpl.changeMonitoringCellCmd))
			    rearrangeOrdered();
		    }
		});
		add(pm);
		pm.show(this, event.getX(), event.getY());
	    } else if (mouseButton == 1) {                // middle button
	    } else {
		Debug.error("Unknown mouse button.  What the hell is going on?");     // shouldn't reach here.
	    }
	}
}

Mouse handling code

 public  void mouseReleased(MouseEvent event) 
{

}

We don't care about these events

 public  void newCellInfo(Vector v) 
{
    // V is a vector of CellListInfo types.
	Enumeration e = v.elements();
	while (e.hasMoreElements()) {
	    CellListInfo cli = (CellListInfo)e.nextElement();
	    if ( !cellInfo.containsKey(cli.getAddress()) ) {
		cellInfo.put(cli.getAddress(), cli);
		addUnmonitoredCell(cli.getAddress());
		rearrangeOrdered();
	    }
	}	
	render( getGraphics() );
}

Called by the CellListAgentImpl in its update loop,

 public  void render(Graphics g) 
{
	//	printCOLS();
	if (g == null) return;
	Point pos = new Point(5, 15);
	Color oldCol = g.getColor();
	Color bg = getBackground();
	g.setColor(bg);
	g.fillRect(0, 0, this.getSize().width, this.getSize().height);
	// Now, go through and render them all.
	Enumeration e = orderedCells.elements();
	while (e.hasMoreElements()) {
 	    CellAddress cell = (CellAddress)e.nextElement();
	    ((Rectangle)cellRects.get(cell)).setLocation(pos.x - 5, pos.y - 15);
	    g.setColor( pickTextCol(bg) );
	    // Draw the name of the cell first
	    String name = stripName(cell.toString());
	    g.drawString(name, pos.x, pos.y);
	    pos.y += 5;      // jump down 5
	    // If the agent is being monitored, draw a colored, raised box.
	    if (monitoredCells.contains(cell)) {
		g.setColor((Color)cellColors.get(cell));
		g.fill3DRect(pos.x, pos.y, 15, 15, true);
	    }
	    else {
		g.setColor(unmonitoredCellColor);
		g.fill3DRect(pos.x, pos.y, 15, 15, false);
	    }
	    //  If not, draw a gray sunken one.
	    pos.x += 25;     // Move 10 beyond edge of the rect
	    pos.y += 12;     // Move down 12 pixels from the top edge of the rectangle
	    g.setColor( pickTextCol(bg) );
	    if (cellInfo.containsKey(cell)) {
		CellListInfo tcli = (CellListInfo)cellInfo.get(cell);
		String outString = (tcli.isUp() ? "up" : "down");
		g.drawString( outString, pos.x, pos.y );
	    }
	    pos.y += 30;
	    pos.x = 5;
	}
	g.setColor(oldCol);
}

 public  void stopMonitoringCell(CellAddress cell) 
{
 
	cellColors.remove( cell ); 
	monitoredCells.removeElement( cell );
	cellRects.remove( cell );
	rearrangeOrdered();
}

Remove a cell and its appropriate color from the database.