Design Patterns By Example in Java- Mediator Pattern : Mediator Pattern « Design Pattern « Java

Home
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.JavaFX
25.JDK 6
26.JDK 7
27.JNDI LDAP
28.JPA
29.JSP
30.JSTL
31.Language Basics
32.Network Protocol
33.PDF RTF
34.Reflection
35.Regular Expressions
36.Scripting
37.Security
38.Servlets
39.Spring
40.Swing Components
41.Swing JFC
42.SWT JFace Eclipse
43.Threads
44.Tiny Application
45.Velocity
46.Web Services SOA
47.XML
Java » Design Pattern » Mediator Pattern 




Design Patterns By Example in Java- Mediator Pattern
Design Patterns By Example in Java- Mediator Pattern

/*

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 javax.swing.DefaultListModel;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.ListSelectionModel;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;

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

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

  public static final String UPLOAD = "Upload";

  public static final String DOWNLOAD = "Download";

  public static final String DELETE "Delete";

  public static final String EXIT = "Exit";

  private JPanel pnlFTPUI;

  private LocalList localList;

  private RemoteList remoteList;

  private DefaultListModel defLocalList, defRemoteList;

  private Mediator mdtr = new Mediator();

  public MediatorPatternFTPGUI() throws Exception {
    super("Design Patterns By Example - Mediator Pattern ");

    // Create controls
    defLocalList = new DefaultListModel();
    defRemoteList = new DefaultListModel();
    localList = new LocalList(defLocalList, mdtr);
    remoteList = new RemoteList(defRemoteList, mdtr);
    pnlFTPUI = new JPanel();

    localList.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
    localList.setSelectedIndex(-1);
    JScrollPane spLocalList = new JScrollPane(localList);

    remoteList.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
    remoteList.setSelectedIndex(-1);
    JScrollPane spRemoteList = new JScrollPane(remoteList);

    //Create Labels
    JLabel lblLocalList = new JLabel("Local List:");
    JLabel lblRemoteList = new JLabel("Remote List:");
    JLabel lblSpacer = new JLabel("         ");

    //Create buttons
    UploadButton btnUpload = new UploadButton(MediatorPatternFTPGUI.UPLOAD,
        mdtr);
    btnUpload.setMnemonic(KeyEvent.VK_U);
    DownloadButton btnDownload = new DownloadButton(
        MediatorPatternFTPGUI.DOWNLOAD, mdtr);
    btnDownload.setMnemonic(KeyEvent.VK_N);
    DeleteButton btnDelete = new DeleteButton(MediatorPatternFTPGUI.DELETE,
        mdtr);
    btnDelete.setMnemonic(KeyEvent.VK_D);
    JButton btnExit = new JButton(MediatorPatternFTPGUI.EXIT);
    btnExit.setMnemonic(KeyEvent.VK_X);

    buttonHandler vf = new buttonHandler();
    listHandler lh = new listHandler();

    btnUpload.addActionListener(vf);
    btnDownload.addActionListener(vf);
    btnDelete.addActionListener(vf);
    btnExit.addActionListener(vf);
    localList.addListSelectionListener(lh);
    remoteList.addListSelectionListener(lh);

    JPanel lstPanel = new JPanel();

    GridBagLayout gridbag2 = new GridBagLayout();
    lstPanel.setLayout(gridbag2);
    GridBagConstraints gbc2 = new GridBagConstraints();
    lstPanel.add(lblLocalList);
    lstPanel.add(lblRemoteList);
    lstPanel.add(spLocalList);
    lstPanel.add(spRemoteList);
    lstPanel.add(lblSpacer);

    gbc2.gridx = 0;
    gbc2.gridy = 0;
    gridbag2.setConstraints(lblLocalList, gbc2);
    gbc2.gridx = 1;
    gbc2.gridy = 0;
    gridbag2.setConstraints(lblSpacer, gbc2);

    gbc2.gridx = 5;
    gbc2.gridy = 0;
    gridbag2.setConstraints(lblRemoteList, gbc2);
    gbc2.gridx = 0;
    gbc2.gridy = 1;
    gridbag2.setConstraints(spLocalList, gbc2);
    gbc2.gridx = 5;
    gbc2.gridy = 1;
    gridbag2.setConstraints(spRemoteList, gbc2);

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

    //----------------------------------------------
    GridBagLayout gridbag = new GridBagLayout();
    buttonPanel.setLayout(gridbag);
    GridBagConstraints gbc = new GridBagConstraints();
    buttonPanel.add(lstPanel);
    buttonPanel.add(btnUpload);
    buttonPanel.add(btnDownload);
    buttonPanel.add(btnDelete);
    buttonPanel.add(btnExit);

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

    gbc.anchor = GridBagConstraints.WEST;
    gbc.gridx = 1;
    gbc.gridy = 0;
    gridbag.setConstraints(btnUpload, gbc);
    gbc.gridx = 2;
    gbc.gridy = 0;
    gridbag.setConstraints(btnDownload, gbc);
    gbc.gridx = 3;
    gbc.gridy = 0;
    gridbag.setConstraints(btnDelete, gbc);
    gbc.gridx = 4;
    gbc.gridy = 0;
    gridbag.setConstraints(btnExit, gbc);

    gbc.gridx = 0;
    gbc.gridy = 1;
    gridbag.setConstraints(lstPanel, gbc);

    gbc.anchor = GridBagConstraints.EAST;
    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(lstPanel, BorderLayout.CENTER);
    contentPane.add(buttonPanel, BorderLayout.SOUTH);

    btnUpload.setEnabled(false);
    btnDelete.setEnabled(false);
    btnDownload.setEnabled(false);

    initialize();
    try {
      UIManager.setLookAndFeel(new WindowsLookAndFeel());
      SwingUtilities.updateComponentTreeUI(MediatorPatternFTPGUI.this);
    catch (Exception ex) {
      System.out.println(ex);
    }

  }

  private void initialize() {
    // fill some test data here into the listbox.
    defLocalList.addElement("first.html");
    defLocalList.addElement("second.html");
    defLocalList.addElement("third.html");
    defLocalList.addElement("fourth.html");
    defLocalList.addElement("fifth.html");
    defLocalList.addElement("Design Patterns.html");

    defRemoteList.addElement("sixth.html");
    defRemoteList.addElement("seventh.html");
    defRemoteList.addElement("eighth.html");
    defRemoteList.addElement("ninth.html");
    defRemoteList.addElement("Design Patterns By Ex.html");

  }

  public static void main(String[] argsthrows Exception {

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

    //frame.pack();
    frame.setSize(450300);
    frame.setVisible(true);
  }

  class listHandler implements ListSelectionListener {
    public void valueChanged(ListSelectionEvent e) {
      CommandInterface CommandObj = (CommandInterfacee.getSource();
      CommandObj.processEvent();
    }

  }

  class buttonHandler implements ActionListener {
    public void actionPerformed(ActionEvent e) {

      if (e.getActionCommand().equals(MediatorPatternFTPGUI.EXIT)) {
        System.exit(1);
      }
      CommandInterface CommandObj = (CommandInterfacee.getSource();
      CommandObj.processEvent();
    }

    public buttonHandler() {
    }
  }

  interface CommandInterface {
    public void processEvent();
  }

  class UploadButton extends JButton implements CommandInterface {
    Mediator mdtr;

    public void processEvent() {
      mdtr.UploadItem();
    }

    public UploadButton(String name, Mediator inp_mdtr) {
      super(name);
      mdtr = inp_mdtr;
      mdtr.registerUploadButton(this);
    }
  }

  class DownloadButton extends JButton implements CommandInterface {
    Mediator mdtr;

    public void processEvent() {
      mdtr.DownloadItem();
    }

    public DownloadButton(String name, Mediator inp_mdtr) {
      super(name);
      mdtr = inp_mdtr;
      mdtr.registerDownloadButton(this);
    }
  }

  class DeleteButton extends JButton implements CommandInterface {
    Mediator mdtr;

    public void processEvent() {
      mdtr.DeleteItem();
    }

    public DeleteButton(String name, Mediator inp_mdtr) {
      super(name);
      mdtr = inp_mdtr;
      mdtr.registerDeleteButton(this);
    }
  }

  class LocalList extends JList implements CommandInterface {
    Mediator mdtr;

    public void processEvent() {
      mdtr.LocalListSelect();
    }

    public LocalList(DefaultListModel defObj, Mediator inp_mdtr) {
      super(defObj);
      mdtr = inp_mdtr;
      mdtr.registerLocalList(this);
    }
  }

  class RemoteList extends JList implements CommandInterface {
    Mediator mdtr;

    public void processEvent() {
      mdtr.RemoteListSelect();
    }

    public RemoteList(DefaultListModel defObj, Mediator inp_mdtr) {
      super(defObj);
      mdtr = inp_mdtr;
      mdtr.registerRemoteList(this);
    }
  }

  class Mediator {
    private UploadButton btnUpload;

    private DownloadButton btnDownload;

    private DeleteButton btnDelete;

    private LocalList localList;

    private RemoteList remoteList;

    public void registerUploadButton(UploadButton inp_ib) {
      btnUpload = inp_ib;
    }

    public void registerDownloadButton(DownloadButton inp_dnb) {
      btnDownload = inp_dnb;
    }

    public void registerDeleteButton(DeleteButton inp_db) {
      btnDelete = inp_db;
    }

    public void registerLocalList(LocalList inp_arl) {
      localList = inp_arl;
    }

    public void registerRemoteList(RemoteList inp_drl) {
      remoteList = inp_drl;
    }

    public void UploadItem() {

      int index = localList.getSelectedIndex();
      String selectedItem = localList.getSelectedValue().toString();
      ((DefaultListModellocalList.getModel()).remove(index);

      ((DefaultListModelremoteList.getModel()).addElement(selectedItem);

      btnUpload.setEnabled(false);
      btnDelete.setEnabled(false);
      btnDownload.setEnabled(false);
    }

    public void DownloadItem() {
      int index = remoteList.getSelectedIndex();
      String selectedItem = remoteList.getSelectedValue().toString();
      ((DefaultListModelremoteList.getModel()).remove(index);

      ((DefaultListModellocalList.getModel()).addElement(selectedItem);

      btnUpload.setEnabled(false);
      btnDelete.setEnabled(false);
      btnDownload.setEnabled(false);
    }

    public void DeleteItem() {
      int index = localList.getSelectedIndex();
      if (index >= 0) {
        ((DefaultListModellocalList.getModel()).remove(index);
      }

      index = remoteList.getSelectedIndex();
      if (index >= 0) {
        ((DefaultListModelremoteList.getModel()).remove(index);
      }
      btnUpload.setEnabled(false);
      btnDelete.setEnabled(false);
      btnDownload.setEnabled(false);

    }

    public void LocalListSelect() {
      remoteList.setSelectedIndex(-1);
      btnUpload.setEnabled(true);
      btnDelete.setEnabled(true);
      btnDownload.setEnabled(false);
    }

    public void RemoteListSelect() {
      localList.setSelectedIndex(-1);
      btnUpload.setEnabled(false);
      btnDelete.setEnabled(true);
      btnDownload.setEnabled(true);
    }
  }

}// end of class



           
       














Related examples in the same category
1.Mediator pattern in JavaMediator pattern in Java
2.Mediator Pattern 2Mediator Pattern 2
java2s.com  | Contact Us | Privacy Policy
Copyright 2009 - 12 Demo Source and Support. All rights reserved.
All other trademarks are property of their respective owners.