private void init(){
		
		setLayout(gridLayout);
		nameLabel=new JLabel("name: ");
		priceLabel=new JLabel("price: ");
		quantityLabel=new JLabel("quantity: ");
		descriptionLabel=new JLabel("description: ");
		nameTextField=new JTextField();
		
		priceTextField=new JTextField();
		priceTextField.addKeyListener(new KeyAdapter() {
            public void keyTyped(KeyEvent e) {
                char vChar = e.getKeyChar();
                if (!(Character.isDigit(vChar)
                        || (vChar == KeyEvent.VK_BACK_SPACE)
                        || (vChar == KeyEvent.VK_DELETE))) {
                    e.consume();
                }
            }
        });
		quantityTextField=new JTextField();
		quantityTextField.addKeyListener(new KeyAdapter() {
            public void keyTyped(KeyEvent e) {
                char vChar = e.getKeyChar();
                if (!(Character.isDigit(vChar)
                        || (vChar == KeyEvent.VK_BACK_SPACE)
                        || (vChar == KeyEvent.VK_DELETE))) {
                    e.consume();
                }
            }
        });
		descriptionTextField=new JTextField();
		add(nameLabel);
		add(nameTextField);
		add(priceLabel);
		add(priceTextField);
		add(quantityLabel);
		add(quantityTextField);
		add(descriptionLabel);
		add(descriptionTextField);
		
	}