@Override
	public void mouseMoved(MouseEvent arg0) {
		// TODO Auto-generated method stub
		int x = arg0.getX()-xOffset;
		int y = arg0.getY()-yOffset;
		toolTip.setVisible(false);
		for(int i=0; i<books.size();i++){
			if(books.get(i).contains(x,y)){
				Point p = arg0.getPoint();
				SwingUtilities.convertPointToScreen(p,this);
				toolTipContent.removeAll();
				toolTipContent.setLayout(new BorderLayout());
				toolTipLabel.setText(books.get(i).getToolTip());
				toolTipLabel.setBackground(Color.white);
				toolTipContent.add(toolTipLabel,BorderLayout.NORTH);
				toolTipContent.add(new Histogram(books.get(i).getBars()),BorderLayout.CENTER);
				toolTip.setLocation((int)p.getX()+2,(int)(p.getY()-toolTip.getHeight()-2));
				toolTip.repaint();
				toolTip.pack();
				//toolTip.setSize(new Dimension(200,500));
				toolTip.setVisible(true);
			}
		}
	}