The MDI Class

This class is used to create the main window of our application.

Listing 16.2 MDI.java

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.rmi.*;

//Main form MDI
public class MDI extends JFrame{
	
  //{{DECLARE CONTROLS}}//
  Container cp=null;
  JDesktopPane dp=null;
  public static MDI mdi=null;
  private static DatabaseInterface server;
	
  //Constructor
  public MDI(){
		
	super("Student Information System");		
		
	//get a content pane object.
	cp = getContentPane();
		
	//Create a new JDesktopPane object.
	//A JDesktopPane object is used 
	//to create a multiple-document 
	//interface or a virtual desktop. 
	dp = new JDesktopPane();
		
	//add the JDesktopPane object 
	//to the content pane.
	cp.add(dp);
		
	//set the background color 
	//of the JDesktopPane object.
	dp.setBackground(cp.getBackground());
		
	//Set the operation that will 
	//happen by default when 
	//the user initiates a "close" 
	//on this frame		
	 setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	 
	 setup();	
	}
		
  //method used to get a reference to the remote object.
  private void setup(){
		
	//method used to create various components
	createMenuComponents();
		
	//method used to set the size of the MDI form
	setMDISize();
	
	//Make the Window visible.
	show();
		
	try{
		 
	  //Get a reference to the remote object 
	  //associated with the specified name.
	  server = (DatabaseInterface)Naming.lookup("DatabaseServer");
		 
	}catch(Exception ex){
		JOptionPane.showMessageDialog(mdi,ex.getMessage()
	 	,"ERROR",JOptionPane.ERROR_MESSAGE);
	} 
		
    }
	
  //This method returns a reference to the remote object
  public static DatabaseInterface getServerObject(){
	return server;
  }

//Method used to create menu bar, menus, and menu items.
 private void createMenuComponents(){
		
 	//create a menu bar object.
	JMenuBar mBar = new JMenuBar();
	 
	//create a menu object
	JMenu mnuForms = SwingComp.createMenu(mBar,"Forms");
	 
	//create an object to handle action events
	MenuHandler mHandler = new MenuHandler();
	 
	//create a menu item object
	JMenuItem 
	 itmStudent = 
	     SwingComp.createMenuItems(mnuForms,mHandler,"Student");
	 
	//Set the menubar for this frame.
	 this.setJMenuBar(mBar); 
   }
	
  //method used to the set size of MDI
  private void setMDISize(){

	//get the default toolkit 
	//to interact with operating system
	Toolkit tk=Toolkit.getDefaultToolkit();
		
	//Get the size of the screen.
	Dimension d = tk.getScreenSize();
	int screenHeight = d.height;
	int screenWidth = d.width;
		
	//set the size of window
	this.setSize(screenWidth,screenHeight);
		
  }	

  //main method 
  static public void main(String args[]){
	mdi= new MDI();
   }
	
  //{{Listener class
  private class MenuHandler 
	implements ActionListener{

    //Invoked when an action occurs.
    public void actionPerformed(ActionEvent ae){
	 
	//create a StudentForm object. 
	StudentForm sf = new StudentForm();

	//method used to show an internal frame
	showForms(sf);
     }
		
   }
	
   //Method used to show an internal frame
   private void showForms(JInternalFrame jif){
   
	dp.add(jif,JLayeredPane.DEFAULT_LAYER);
	try{

	   //show the internal frame window
	   jif.show();
		 
	   //Select the JInternalFrame. 
	   jif.setSelected(true); 
				 
	 }catch(java.beans.PropertyVetoException ex){
	     JOptionPane.showMessageDialog(
		mdi,ex.getLocalizedMessage());
	 }
     }
	
  }