edit my java code so that historyEntry is added to a list which I can then show on the Jlabel Commande: 	import java.awt.EventQueue;


public class PizzaOrder extends JFrame {


	private JPanel contentPane;
	private JTextField NumPizza;
	private JTextField NumTopping;
	private JTextField NumBreuvage;
	private JButton Ajouter;
	private double totales;
	private String History;
	private static String previousHistory;



	public static void main(String[] args) {
		EventQueue.invokeLater(new Runnable() {
			public void run() {
				try {
					PizzaOrder frame = new PizzaOrder(previousHistory);
					frame.setVisible(true);
				} catch (Exception e) {
					e.printStackTrace();

				}
			}
		});

	}


	public PizzaOrder(String previousHistory) {
	    History = previousHistory;

		setTitle("Order");
		setResizable(false);
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		setBounds(100, 100, 630, 689);
		contentPane = new JPanel();
		contentPane.setBackground(new Color(255, 147, 0));
		contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));

		setContentPane(contentPane);
		contentPane.setLayout(null);

		JPanel Menu = new JPanel();
		Menu.setBackground(new Color(255, 147, 0));
		Menu.setBorder(new TitledBorder(new LineBorder(new Color(0, 0, 0)), "Menu", TitledBorder.LEADING, TitledBorder.TOP, null, new Color(0, 0, 0)));
		Menu.setBounds(6, 6, 618, 158);
		contentPane.add(Menu);
		Menu.setLayout(new GridLayout(0, 3, 0, 0));

		JPanel PizzaPrice = new JPanel();
		PizzaPrice.setBackground(new Color(255, 147, 0));
		PizzaPrice.setBorder(new TitledBorder(new EtchedBorder(EtchedBorder.LOWERED, null, null), "Pizza", TitledBorder.LEADING, TitledBorder.TOP, null, null));
		Menu.add(PizzaPrice);
		PizzaPrice.setLayout(null);

		JLabel PetitPizza = new JLabel("Petit: 6.79$");
		PetitPizza.setBounds(17, 21, 72, 16);
		PizzaPrice.add(PetitPizza);

		JLabel MoyenPizza = new JLabel("Moyen: 8.29$");
		MoyenPizza.setBounds(17, 40, 85, 16);
		PizzaPrice.add(MoyenPizza);

		JLabel LargePizza = new JLabel("Large: 9.49$");
		LargePizza.setBounds(17, 59, 85, 16);
		PizzaPrice.add(LargePizza);

		JLabel ExtraLargePizza = new JLabel("Extra Large: 10.29$");
		ExtraLargePizza.setBounds(17, 78, 127, 16);
		PizzaPrice.add(ExtraLargePizza);

		JLabel FetePizza = new JLabel("Fete: 15.99$");
		FetePizza.setBounds(17, 97, 93, 16);
		PizzaPrice.add(FetePizza);

		JPanel ToppingPrice = new JPanel();
		ToppingPrice.setBackground(new Color(255, 147, 0));
		ToppingPrice.setLayout(null);
		ToppingPrice.setBorder(new TitledBorder(new EtchedBorder(EtchedBorder.LOWERED, null, null), "Toppings", TitledBorder.LEADING, TitledBorder.TOP, null, new Color(0, 0, 0)));
		Menu.add(ToppingPrice);

		JLabel Petittopping = new JLabel("Petit: 1.20$");
		Petittopping.setBounds(17, 21, 72, 16);
		ToppingPrice.add(Petittopping);

		JLabel Moyentopping = new JLabel("Moyen: 1.40$");
		Moyentopping.setBounds(17, 40, 85, 16);
		ToppingPrice.add(Moyentopping);

		JLabel Largetopping = new JLabel("Large: 1.60$");
		Largetopping.setBounds(17, 59, 85, 16);
		ToppingPrice.add(Largetopping);

		JLabel ExtraLargetopping = new JLabel("Extra Large: 1.80$");
		ExtraLargetopping.setBounds(17, 78, 127, 16);
		ToppingPrice.add(ExtraLargetopping);

		JLabel Fetetopping = new JLabel("Fete: 2.30$");
		Fetetopping.setBounds(17, 97, 93, 16);
		ToppingPrice.add(Fetetopping);

		JPanel BreuvagePrice = new JPanel();
		BreuvagePrice.setBackground(new Color(255, 147, 0));
		BreuvagePrice.setLayout(null);
		BreuvagePrice.setBorder(new TitledBorder(new EtchedBorder(EtchedBorder.LOWERED, null, null), "Breuvages", TitledBorder.LEADING, TitledBorder.TOP, null, new Color(0, 0, 0)));
		Menu.add(BreuvagePrice);

		JLabel Pop = new JLabel("Pop: 1.10$");
		Pop.setBounds(17, 21, 72, 16);
		BreuvagePrice.add(Pop);

		JLabel Jus = new JLabel("Jus: 1.35$");
		Jus.setBounds(17, 40, 85, 16);
		BreuvagePrice.add(Jus);

		JLabel Eau = new JLabel("Eau: 1.00$");
		Eau.setBounds(17, 59, 85, 16);
		BreuvagePrice.add(Eau);

		JPanel PizzaSelect = new JPanel();
		PizzaSelect.setBorder(new SoftBevelBorder(BevelBorder.LOWERED, null, null, null, null));
		PizzaSelect.setBackground(new Color(255, 147, 0));
		PizzaSelect.setBounds(16, 187, 350, 300);
		contentPane.add(PizzaSelect);
		PizzaSelect.setLayout(null);


		JComboBox<String> ChoixPizza = new JComboBox<String>();
		ChoixPizza.setModel(new DefaultComboBoxModel(PizzaSize.values()));
		ChoixPizza.setBounds(44, 8, 126, 27);
		ChoixPizza.setMaximumRowCount(5);
		PizzaSelect.add(ChoixPizza);


		NumPizza = new JTextField();
		NumPizza.setText("0");
		NumPizza.setBounds(175, 8, 130, 26);
		PizzaSelect.add(NumPizza);
		NumPizza.setColumns(10);

		JLabel PizzaIcon = new JLabel("");
		PizzaIcon.setBounds(6, 6, 350, 279);
		PizzaSelect.add(PizzaIcon);
		PizzaIcon.setIcon(new ImageIcon(PizzaOrder.class.getResource("/Image/PizzaImage.png")));

		JPanel ToppingSelect;
		ToppingSelect = new JPanel();
		ToppingSelect.setBorder(new SoftBevelBorder(BevelBorder.LOWERED, null, null, null, null));
		ToppingSelect.setBackground(new Color(255, 147, 0));
		ToppingSelect.setBounds(400, 187, 208, 129);
		contentPane.add(ToppingSelect);
		ToppingSelect.setLayout(null);

		JComboBox<String> ChoixTopping = new JComboBox<String>();;
		ChoixTopping.setModel(new DefaultComboBoxModel(ToppingSize.values()));
		ChoixTopping.setBounds(41, 8, 126, 27);
		ChoixTopping.setMaximumRowCount(5);
		ToppingSelect.add(ChoixTopping);

		NumTopping = new JTextField();
		NumTopping.setText("0");
		NumTopping.setBounds(39, 40, 130, 26);
		NumTopping.setColumns(10);
		ToppingSelect.add(NumTopping);

		JLabel ToppingIcon = new JLabel("");
		ToppingIcon.setIcon(new ImageIcon(PizzaOrder.class.getResource("/Image/ToppingImage.png")));
		ToppingIcon.setBounds(6, 8, 208, 109);
		ToppingSelect.add(ToppingIcon);

		JPanel BreuvageSelect = new JPanel();
		BreuvageSelect.setBorder(new SoftBevelBorder(BevelBorder.LOWERED, null, null, null, null));
		BreuvageSelect.setBackground(new Color(255, 147, 0));
		BreuvageSelect.setBounds(400, 358, 208, 129);
		contentPane.add(BreuvageSelect);
		BreuvageSelect.setLayout(null);

		JComboBox<String> ChoixBreuvage = new JComboBox<String>();;
		ChoixBreuvage.setModel(new DefaultComboBoxModel(Breuvages.values()));
		ChoixBreuvage.setBounds(64, 8, 79, 27);
		ChoixBreuvage.setMaximumRowCount(3);
		BreuvageSelect.add(ChoixBreuvage);

		NumBreuvage = new JTextField();
		NumBreuvage.setText("0");
		NumBreuvage.setBounds(39, 40, 130, 26);
		NumBreuvage.setColumns(10);
		BreuvageSelect.add(NumBreuvage);

		JLabel BreuvageIcon = new JLabel("");
		BreuvageIcon.setIcon(new ImageIcon(PizzaOrder.class.getResource("/Image/BreuvageImage.png")));
		BreuvageIcon.setBounds(0, 0, 209, 129);
		BreuvageSelect.add(BreuvageIcon);



		Ajouter = new JButton("Ajouter");
		Ajouter.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent e) {
				// retrieve selected values from combo boxes
				PizzaSize selectedPizzaSize = (PizzaSize) ChoixPizza.getSelectedItem();
				ToppingSize selectedToppingSize = (ToppingSize) ChoixTopping.getSelectedItem();
				Breuvages selectedBreuvage = (Breuvages) ChoixBreuvage.getSelectedItem();
				int numPizza = Integer.parseInt(NumPizza.getText());
				int numTopping = Integer.parseInt(NumTopping.getText());
				int numBreuvage = Integer.parseInt(NumBreuvage.getText());

				// calculate total amount

				totales += selectedPizzaSize.getPrice() * numPizza;
				totales += selectedToppingSize.getPrice() * numTopping;
				totales += selectedBreuvage.getPrice() * numBreuvage;
		
				
		        double historytotal = (numPizza * selectedPizzaSize.getPrice()) + (numTopping * selectedToppingSize.getPrice() + (numBreuvage * selectedBreuvage.getPrice()));
		        String historyEntry = numPizza + " Pizza de taille " + selectedPizzaSize + " avec " + numTopping + " " + selectedToppingSize + " \ngarniture - Cout: " + historytotal;
		        
		    

		     // clear text fields
				NumPizza.setText("0");
				NumTopping.setText("0");
				NumBreuvage.setText("0");
				
				
				
			}	
		});
		Ajouter.setBounds(234, 552, 160, 50);
		contentPane.add(Ajouter);
		
		

		JButton Quitter = new JButton("Quitter");
		Quitter.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent e) {
				System.exit(0);
			}
		});
		Quitter.setBounds(33, 552, 160, 50);
		contentPane.add(Quitter);


		JButton Payer = new JButton("Payer");
		Payer.setBounds(431, 552, 160, 50);
		contentPane.add(Payer);	
		Payer.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent e) {
				    Receipt receiptWindow = new Receipt(totales, History);
			        receiptWindow.setVisible(true);
			        setVisible(false);
			           
			}
		});
	}	
}
import java.awt.EventQueue;


public class Receipt extends JFrame {

	private double totales;
	private String history;
	private JPanel contentPane;
	private JTable table;
	private DefaultTableModel model;
	private static String previousHistory;

	


    public Receipt(double totales, String history) {
    
    	
    	this.totales = totales;
    	this.history=history;
    	
		setResizable(false);
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		setBounds(100, 100, 680, 440);
		contentPane = new JPanel();
		contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));

		setContentPane(contentPane);
		contentPane.setLayout(null);

		
		JPanel panel = new JPanel();
		panel.setBounds(81, 23, 496, 368);	
		panel.setBackground(new Color(254, 255, 255));
		panel.setBorder(null);
		contentPane.add(panel);
		panel.setLayout(null);
		

		
		JLabel Order = new JLabel("Commande:");
		Order.setHorizontalAlignment(SwingConstants.CENTER);
		Order.setFont(new Font("Zapfino", Font.PLAIN, 13));
		Order.setBounds(118, 24, 283, 29);
		panel.add(Order);
		
		
		 
		    
		 String formattedTotal = String.format("%.2f", totales * 1.13);
		 
			JLabel Total = new JLabel("Total +Tax: " + formattedTotal);
			Total.setFont(new Font("Lucida Grande", Font.BOLD, 13));
			Total.setBounds(147, 283, 182, 21);
			panel.add(Total);
			Total.setVisible(false);


			



	        JTextArea commandArea = new JTextArea();
	        commandArea.setFont(new Font("Monospaced", Font.PLAIN, 12));
	        commandArea.setEditable(false);
	        commandArea.setLineWrap(true);
	        commandArea.setText(history);

	        JScrollPane scrollPane = new JScrollPane(commandArea);
	        scrollPane.setBounds(86, 78, 315, 168);
	        panel.add(scrollPane);
	        scrollPane.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
			scrollPane.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);
			commandArea.setPreferredSize(new Dimension(300, 200));
		
			JLabel Commande = new JLabel(history);
			Commande.setHorizontalAlignment(SwingConstants.LEFT);
			Commande.setVerticalAlignment(SwingConstants.TOP);
			Commande.setBounds(86, 78, 315, 168);
			panel.add(Commande);
			

		
		JButton modifierCommande = new JButton("Modifier commande");
		modifierCommande.setBounds(6, 316, 182, 29);
		panel.add(modifierCommande);
		modifierCommande.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent e) {
				setVisible(false);
				PizzaOrder PizzaOrderWindow = new PizzaOrder(previousHistory);
				PizzaOrderWindow.setVisible(true);
			}
		});
		
		
		JButton Quitter = new JButton("Fermer");
		Quitter.setBounds(367, 316, 101, 29);
		panel.add(Quitter);
		
		JLabel Totale = new JLabel("Total: " + totales);
		Totale.setFont(new Font("Lucida Grande", Font.BOLD, 13));
		Totale.setBounds(147, 262, 86, 21);
		panel.add(Totale);
		
		JButton btntax = new JButton("+Tax(13%)");
		btntax.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent e) {
				Total.setVisible(true);
			}
		});
		btntax.setBounds(228, 259, 101, 29);
		panel.add(btntax);
		
		
		Quitter.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent e) {
				System.exit(0);
				Total.setVisible(false);
			}
		});


	}
    
    /**
	 * Launch the application.
	 */
	public static void main(String[] args) {
		EventQueue.invokeLater(new Runnable() {
			public void run() {
				try {
					Receipt frame = new Receipt(0,"");
					frame.setVisible(true);
				} catch (Exception e) {
					e.printStackTrace();
				}
			}
		});
	}
}