Problems passing an object through private classes

I keep getting a Null exception after trying to submit data entered by radio buttons. It appears the setters aren't working in my radio button listeners, and I'm not sure why.

// ***********************************

// OrderPanel.java

//

// Creates an interface for ordering

// objects from a restaurant, using

// radio buttons and a JButton.

//

// ***********************************


import javax.swing.*;

import java.awt.*;

import java.awt.event.*;


public class OrderPanel extends JPanel

{

	// creating graphical components

	private JRadioButton pizza, beverage, mozzSticks, breadSticks, small, medium, large;

	private JLabel totalPrice;

	private JButton order;

	

	private static int count = 0;

	private static int total = 0;

	

	public static FoodItem orderUp = new FoodItem();

	

	public OrderPanel()

	{

		

		totalPrice = new JLabel("Total ");

		

		order = new JButton("Order");

		ButtonListener buttonListen = new ButtonListener();

		order.addActionListener(buttonListen);

	

		// all the items available for order

		pizza = new JRadioButton("Pizza", true);

		pizza.setBackground(Color.red);

		beverage = new JRadioButton("Beverage");

		beverage.setBackground(Color.red);

		mozzSticks = new JRadioButton("Mozzarella Sticks");

		mozzSticks.setBackground(Color.red);

		breadSticks = new JRadioButton("Breadsticks");

		breadSticks.setBackground(Color.red);

	

		// grouping order items

		ButtonGroup items = new ButtonGroup();

		items.add(pizza);

		items.add(beverage);

		items.add(mozzSticks);

		items.add(breadSticks);

		

		// listening

		ItemListener itemListen = new ItemListener();

		pizza.addActionListener(itemListen);

		beverage.addActionListener(itemListen);

		mozzSticks.addActionListener(itemListen);

		breadSticks.addActionListener(itemListen);

	

		// size of item to be ordered

		small = new JRadioButton("Small", true);

		small.setBackground(Color.red);

		medium = new JRadioButton("Medium");

		medium.setBackground(Color.red);

		large = new JRadioButton("Large");

		large.setBackground(Color.red);

		

		SizeListener sizeListen = new SizeListener();

		small.addActionListener(sizeListen);

		medium.addActionListener(sizeListen);

		large.addActionListener(sizeListen);

	

		ButtonGroup sizes = new ButtonGroup();

		sizes.add(small);

		sizes.add(medium);

		sizes.add(large);

		

		// adding all the radio buttons and the order button to the frame

		add(pizza);

		add(beverage);

		add(mozzSticks);

		add(breadSticks);

		

		add(small);

		add(medium);

		add(large);

		

		add(totalPrice);

		add(order);

		

		setBackground(Color.RED);

		setPreferredSize(new Dimension (400, 100));

		

		

	}

	

	// listener for items to be ordered

	private class ItemListener implements ActionListener

	{

		public void actionPerformed(ActionEvent event)

		{

			Object source = event.getSource();

			

			// sorting out what has been selected

			if (source == pizza)

			{

				orderUp.setItem("Pizza");

			}

			else if (source == beverage)

			{

				orderUp.setItem("Beverage");

			}

			else if (source == mozzSticks)

			{

				orderUp.setItem("Mozzarella Sticks");

			}

			else if (source == breadSticks)

			{

				orderUp.setItem("Breadsticks");

			}

		}

		

	}

	

	// listener for sizes

	private class SizeListener implements ActionListener

	{

		public void actionPerformed(ActionEvent event)

		{

			Object source = event.getSource();

			

			// sorting out size selected

			if (source == small)

			{

				orderUp.setSize("Small");

			}

			else if (source == medium)

			{

				orderUp.setSize("Medium");

			}

			else if (source == large)

			{

				orderUp.setSize("Large");

			}

		}

	}

	

	// listener for the Order button

	private class ButtonListener implements ActionListener

	{

		public void actionPerformed(ActionEvent event)

		{

			int tempPrice = 0;


			// sets prices according to what the radio buttons have selected

			if (orderUp.getItem().equals("Pizza"))

			{

				if (orderUp.getSize().equals("Small"))

				{

					tempPrice = 7;

				}

				else if (orderUp.getSize().equals("Medium"))

				{

					tempPrice = 10;

				}

				else if (orderUp.getSize().equals("Large"))

				{

					tempPrice = 15;

				}

			}

			else if (orderUp.equals("Beverage"))

			{

				if (orderUp.getSize().equals("Small"))

				{

					tempPrice = 2;

				}

				else if (orderUp.getSize().equals("Medium"))

				{

					tempPrice = 3;

				}

				else if (orderUp.getSize().equals("Large"))

				{

					tempPrice = 4;

				}

			}

			else if (orderUp.equals("Mozzarella Sticks"))

			{

				if (orderUp.getSize().equals("Small"))

				{

					tempPrice = 5;

				}

				else if (orderUp.getSize().equals("Medium"))

				{

					tempPrice = 7;

				}

				else if (orderUp.getSize().equals("Large"))

				{

					tempPrice = 9;

				}

			}

			else if (orderUp.equals("Breadsticks"))

			{

				if (orderUp.getSize().equals("Small"))

				{

					tempPrice = 4;

				}

				else if (orderUp.getSize().equals("Medium"))

				{

					tempPrice = 6;

				}

				else if (orderUp.getSize().equals("Large"))

				{

					tempPrice = 8;

				}

			}

			

			// adds the price of the individual order to the total cost of the order

			total += tempPrice;

			totalPrice.setText("Total: " + total);

			count++;

		}

	}

}