Visitor Pattern - Example : Visitor Pattern « Design Pattern « Java

Java
1. 2D Graphics GUI
2. 3D
3. Advanced Graphics
4. Ant
5. Apache Common
6. Chart
7. Class
8. Collections Data Structure
9. Data Type
10. Database SQL JDBC
11. Design Pattern
12. Development Class
13. EJB3
14. Email
15. Event
16. File Input Output
17. Game
18. Generics
19. GWT
20. Hibernate
21. I18N
22. J2EE
23. J2ME
24. JDK 6
25. JNDI LDAP
26. JPA
27. JSP
28. JSTL
29. Language Basics
30. Network Protocol
31. PDF RTF
32. Reflection
33. Regular Expressions
34. Scripting
35. Security
36. Servlets
37. Spring
38. Swing Components
39. Swing JFC
40. SWT JFace Eclipse
41. Threads
42. Tiny Application
43. Velocity
44. Web Services SOA
45. XML
Java Tutorial
Java Source Code / Java Documentation
Java Open Source
Jar File Download
Java Articles
Java Products
Java by API
Photoshop Tutorials
Maya Tutorials
Flash Tutorials
3ds-Max Tutorials
Illustrator Tutorials
GIMP Tutorials
C# / C Sharp
C# / CSharp Tutorial
C# / CSharp Open Source
ASP.Net
ASP.NET Tutorial
JavaScript DHTML
JavaScript Tutorial
JavaScript Reference
HTML / CSS
HTML CSS Reference
C / ANSI-C
C Tutorial
C++
C++ Tutorial
Ruby
PHP
Python
Python Tutorial
Python Open Source
SQL Server / T-SQL
SQL Server / T-SQL Tutorial
Oracle PL / SQL
Oracle PL/SQL Tutorial
PostgreSQL
SQL / MySQL
MySQL Tutorial
VB.Net
VB.Net Tutorial
Flash / Flex / ActionScript
VBA / Excel / Access / Word
XML
XML Tutorial
Microsoft Office PowerPoint 2007 Tutorial
Microsoft Office Excel 2007 Tutorial
Microsoft Office Word 2007 Tutorial
Java » Design Pattern » Visitor PatternScreenshots 
Visitor Pattern - Example

/*

Software Architecture Design Patterns in Java
by Partha Kuchana 

Auerbach Publications


*/


import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.util.Vector;

import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;

import com.sun.java.swing.plaf.windows.WindowsLookAndFeel;

public class OrderManager extends JFrame {
  public static final String newline = "\n";

  public static final String GET_TOTAL = "Get Total";

  public static final String CREATE_ORDER = "Create Order";

  public static final String EXIT = "Exit";

  public static final String CA_ORDER = "California Order";

  public static final String NON_CA_ORDER = "Non-California Order";

  public static final String OVERSEAS_ORDER = "Overseas Order";

  private JComboBox cmbOrderType;

  private JTextField txtOrderAmount, txtAdditionalTax, txtAdditionalSH;

  private JLabel lblOrderType, lblOrderAmount;

  private JLabel lblAdditionalTax, lblAdditionalSH;

  private JLabel lblTotal, lblTotalValue;

  private OrderVisitor objVisitor;

  public OrderManager() {
    super("Visitor Pattern - Example");

    //Create the visitor instance
    objVisitor = new OrderVisitor();

    cmbOrderType = new JComboBox();
    cmbOrderType.addItem(OrderManager.CA_ORDER);
    cmbOrderType.addItem(OrderManager.NON_CA_ORDER);
    cmbOrderType.addItem(OrderManager.OVERSEAS_ORDER);

    txtOrderAmount = new JTextField(10);
    txtAdditionalTax = new JTextField(10);
    txtAdditionalSH = new JTextField(10);

    lblOrderType = new JLabel("Order Type:");
    lblOrderAmount = new JLabel("Order Amount:");
    lblAdditionalTax = new JLabel("Additional Tax(CA Orders Only):");
    lblAdditionalSH = new JLabel("Additional S & H(Overseas Orders Only):");

    lblTotal = new JLabel("Result:");
    lblTotalValue = new JLabel("Click Create or GetTotal Button");

    //Create the open button
    JButton getTotalButton = new JButton(OrderManager.GET_TOTAL);
    getTotalButton.setMnemonic(KeyEvent.VK_G);
    JButton createOrderButton = new JButton(OrderManager.CREATE_ORDER);
    getTotalButton.setMnemonic(KeyEvent.VK_C);
    JButton exitButton = new JButton(OrderManager.EXIT);
    exitButton.setMnemonic(KeyEvent.VK_X);
    ButtonHandler objButtonHandler = new ButtonHandler(this);

    getTotalButton.addActionListener(objButtonHandler);
    createOrderButton.addActionListener(objButtonHandler);
    exitButton.addActionListener(new ButtonHandler());

    //For layout purposes, put the buttons in a separate panel
    JPanel buttonPanel = new JPanel();

    JPanel panel = new JPanel();
    GridBagLayout gridbag2 = new GridBagLayout();
    panel.setLayout(gridbag2);
    GridBagConstraints gbc2 = new GridBagConstraints();
    panel.add(getTotalButton);
    panel.add(createOrderButton);
    panel.add(exitButton);
    gbc2.anchor = GridBagConstraints.EAST;
    gbc2.gridx = 0;
    gbc2.gridy = 0;
    gridbag2.setConstraints(createOrderButton, gbc2);
    gbc2.gridx = 1;
    gbc2.gridy = 0;
    gridbag2.setConstraints(getTotalButton, gbc2);
    gbc2.gridx = 2;
    gbc2.gridy = 0;
    gridbag2.setConstraints(exitButton, gbc2);

    //****************************************************
    GridBagLayout gridbag = new GridBagLayout();
    buttonPanel.setLayout(gridbag);
    GridBagConstraints gbc = new GridBagConstraints();

    buttonPanel.add(lblOrderType);
    buttonPanel.add(cmbOrderType);
    buttonPanel.add(lblOrderAmount);
    buttonPanel.add(txtOrderAmount);
    buttonPanel.add(lblAdditionalTax);
    buttonPanel.add(txtAdditionalTax);
    buttonPanel.add(lblAdditionalSH);
    buttonPanel.add(txtAdditionalSH);
    buttonPanel.add(lblTotal);
    buttonPanel.add(lblTotalValue);

    gbc.insets.top = 5;
    gbc.insets.bottom = 5;
    gbc.insets.left = 5;
    gbc.insets.right = 5;

    gbc.anchor = GridBagConstraints.EAST;
    gbc.gridx = 0;
    gbc.gridy = 0;
    gridbag.setConstraints(lblOrderType, gbc);
    gbc.anchor = GridBagConstraints.WEST;
    gbc.gridx = 1;
    gbc.gridy = 0;
    gridbag.setConstraints(cmbOrderType, gbc);

    gbc.anchor = GridBagConstraints.EAST;
    gbc.gridx = 0;
    gbc.gridy = 1;
    gridbag.setConstraints(lblOrderAmount, gbc);
    gbc.anchor = GridBagConstraints.WEST;
    gbc.gridx = 1;
    gbc.gridy = 1;
    gridbag.setConstraints(txtOrderAmount, gbc);

    gbc.anchor = GridBagConstraints.EAST;
    gbc.gridx = 0;
    gbc.gridy = 2;
    gridbag.setConstraints(lblAdditionalTax, gbc);
    gbc.anchor = GridBagConstraints.WEST;
    gbc.gridx = 1;
    gbc.gridy = 2;
    gridbag.setConstraints(txtAdditionalTax, gbc);

    gbc.anchor = GridBagConstraints.EAST;
    gbc.gridx = 0;
    gbc.gridy = 3;
    gridbag.setConstraints(lblAdditionalSH, gbc);
    gbc.anchor = GridBagConstraints.WEST;
    gbc.gridx = 1;
    gbc.gridy = 3;
    gridbag.setConstraints(txtAdditionalSH, gbc);

    gbc.anchor = GridBagConstraints.EAST;
    gbc.gridx = 0;
    gbc.gridy = 4;
    gridbag.setConstraints(lblTotal, gbc);
    gbc.anchor = GridBagConstraints.WEST;
    gbc.gridx = 1;
    gbc.gridy = 4;
    gridbag.setConstraints(lblTotalValue, gbc);

    gbc.insets.left = 2;
    gbc.insets.right = 2;
    gbc.insets.top = 40;

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

    //Add the buttons and the log to the frame
    Container contentPane = getContentPane();

    contentPane.add(buttonPanel, BorderLayout.NORTH);
    contentPane.add(panel, BorderLayout.CENTER);
    try {
      UIManager.setLookAndFeel(new WindowsLookAndFeel());
      SwingUtilities.updateComponentTreeUI(OrderManager.this);
    catch (Exception ex) {
      System.out.println(ex);
    }

  }

  public static void main(String[] args) {
    JFrame frame = new OrderManager();

    frame.addWindowListener(new WindowAdapter() {
      public void windowClosing(WindowEvent e) {
        System.exit(0);
      }
    });

    //frame.pack();
    frame.setSize(500400);
    frame.setVisible(true);
  }

  public void setTotalValue(String msg) {
    lblTotalValue.setText(msg);
  }

  public OrderVisitor getOrderVisitor() {
    return objVisitor;
  }

  public String getOrderType() {
    return (StringcmbOrderType.getSelectedItem();
  }

  public String getOrderAmount() {
    return txtOrderAmount.getText();
  }

  public String getTax() {
    return txtAdditionalTax.getText();
  }

  public String getSH() {
    return txtAdditionalSH.getText();
  }

// End of class OrderManager

class ButtonHandler implements ActionListener {
  OrderManager objOrderManager;

  public void actionPerformed(ActionEvent e) {
    String totalResult = null;

    if (e.getActionCommand().equals(OrderManager.EXIT)) {
      System.exit(1);
    }
    if (e.getActionCommand().equals(OrderManager.CREATE_ORDER)) {
      //get input values
      String orderType = objOrderManager.getOrderType();
      String strOrderAmount = objOrderManager.getOrderAmount();
      String strTax = objOrderManager.getTax();
      String strSH = objOrderManager.getSH();

      double dblOrderAmount = 0.0;
      double dblTax = 0.0;
      double dblSH = 0.0;

      if (strOrderAmount.trim().length() == 0) {
        strOrderAmount = "0.0";
      }
      if (strTax.trim().length() == 0) {
        strTax = "0.0";
      }
      if (strSH.trim().length() == 0) {
        strSH = "0.0";
      }

      dblOrderAmount = new Double(strOrderAmount).doubleValue();
      dblTax = new Double(strTax).doubleValue();
      dblSH = new Double(strSH).doubleValue();

      //Create the order
      Order order = createOrder(orderType, dblOrderAmount, dblTax, dblSH);

      //Get the Visitor
      OrderVisitor visitor = objOrderManager.getOrderVisitor();

      // accept the visitor instance
      order.accept(visitor);

      objOrderManager.setTotalValue(" Order Created Successfully");
    }

    if (e.getActionCommand().equals(OrderManager.GET_TOTAL)) {
      //Get the Visitor
      OrderVisitor visitor = objOrderManager.getOrderVisitor();
      totalResult = new Double(visitor.getOrderTotal()).toString();
      totalResult = " Orders Total = " + totalResult;
      objOrderManager.setTotalValue(totalResult);
    }
  }

  public Order createOrder(String orderType, double orderAmount, double tax,
      double SH) {
    if (orderType.equalsIgnoreCase(OrderManager.CA_ORDER)) {
      return new CaliforniaOrder(orderAmount, tax);
    }
    if (orderType.equalsIgnoreCase(OrderManager.NON_CA_ORDER)) {
      return new NonCaliforniaOrder(orderAmount);
    }
    if (orderType.equalsIgnoreCase(OrderManager.OVERSEAS_ORDER)) {
      return new OverseasOrder(orderAmount, SH);
    }
    return null;
  }

  public ButtonHandler() {
  }

  public ButtonHandler(OrderManager inObjOrderManager) {
    objOrderManager = inObjOrderManager;
  }

// End of class ButtonHandler

class NonCaliforniaOrder implements Order {
  private double orderAmount;

  public NonCaliforniaOrder() {
  }

  public NonCaliforniaOrder(double inp_orderAmount) {
    orderAmount = inp_orderAmount;
  }

  public double getOrderAmount() {
    return orderAmount;
  }

  public void accept(OrderVisitor v) {
    v.visit(this);
  }
}

class CaliforniaOrder implements Order {
  private double orderAmount;

  private double additionalTax;

  public CaliforniaOrder() {
  }

  public CaliforniaOrder(double inp_orderAmount, double inp_additionalTax) {
    orderAmount = inp_orderAmount;
    additionalTax = inp_additionalTax;
  }

  public double getOrderAmount() {
    return orderAmount;
  }

  public double getAdditionalTax() {
    return additionalTax;
  }

  public void accept(OrderVisitor v) {
    v.visit(this);
  }
}

interface VisitorInterface {
  public void visit(NonCaliforniaOrder nco);

  public void visit(CaliforniaOrder co);

  public void visit(OverseasOrder oo);
}

class OverseasOrder implements Order {
  private double orderAmount;

  private double additionalSH;

  public OverseasOrder() {
  }

  public OverseasOrder(double inp_orderAmount, double inp_additionalSH) {
    orderAmount = inp_orderAmount;
    additionalSH = inp_additionalSH;
  }

  public double getOrderAmount() {
    return orderAmount;
  }

  public double getAdditionalSH() {
    return additionalSH;
  }

  public void accept(OrderVisitor v) {
    v.visit(this);
  }
}

class OrderVisitor implements VisitorInterface {
  private Vector orderObjList;

  private double orderTotal;

  public OrderVisitor() {
    orderObjList = new Vector();
  }

  public void visit(NonCaliforniaOrder inp_order) {
    orderTotal = orderTotal + inp_order.getOrderAmount();
  }

  public void visit(CaliforniaOrder inp_order) {
    orderTotal = orderTotal + inp_order.getOrderAmount()
        + inp_order.getAdditionalTax();
  }

  public void visit(OverseasOrder inp_order) {
    orderTotal = orderTotal + inp_order.getOrderAmount()
        + inp_order.getAdditionalSH();
  }

  public double getOrderTotal() {
    return orderTotal;
  }
}

interface Order {
  public void accept(OrderVisitor v);
}

           
       
Related examples in the same category
1. Visitor Pattern 1
2. Visitor pattern in JavaVisitor pattern in Java
www.java2java.com | Contact Us
Copyright 2009 - 12 Demo Source and Support. All rights reserved.
All other trademarks are property of their respective owners.