@Override
	public void actionPerformed(ActionEvent e) {
		String name = e.getActionCommand();
		if(name=="Sort")
		{
			//title 
			if(r1_sort.isSelected())
			{
				customer.sortBookByTitle();
				GUIInterface.aText_p4.setText(Main.TITLE+Main.array.toString());
			}
			//authorName
			else if(r2_sort.isSelected())
			{
				customer.sortBookByAuthorName();
				GUIInterface.aText_p4.setText(Main.TITLE+Main.array.toString());
			}
			//Stock
			else if(r3_sort.isSelected())
			{
				customer.sortBookByStock();
				GUIInterface.aText_p4.setText(Main.TITLE+Main.array.toString());
			}
			//publishedDate
			else if(r4_sort.isSelected())
			{
				customer.sortBookByPublishedDate();
				GUIInterface.aText_p4.setText(Main.TITLE+Main.array.toString());
			}
			//price
			else if(r5_sort.isSelected())
			{
				customer.sortBookByPrice();
				GUIInterface.aText_p4.setText(Main.TITLE+Main.array.toString());
			}
			//ISBN
			else if(r6_sort.isSelected())
			{
				customer.sortBookByISBN();
				GUIInterface.aText_p4.setText(Main.TITLE+Main.array.toString());
			}
		}
	}