customerage.java

《J2EE专业项目实例开发》源代码

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
// <applet code=CustomerAge width=500 height=200>
// </applet>
class IllegalAgeException extends Exception
{     
      public String getMessage()
      {
          return "Error!!! Invalid Age! ";
}
}
public class CustomerAge extends JApplet
{
 int custAge;
 JPanel panelObject;
 JButton buttonAccept;
 JLabel labelCustAge;
 JTextField textCustAge;

 void setAge(int age) throws IllegalAgeException
 {
    if ((age<20) || (age>60))
          throw new IllegalAgeException();
    custAge=age;
 }
 public void init()
 {
    panelObject=(JPanel)getContentPane();
    panelObject.setLayout(new FlowLayout());
    labelCustAge=new JLabel("Enter Customer Age:");
    textCustAge=new JTextField(5);
    buttonAccept=new JButton("Verify");
    panelObject.add(labelCustAge);
    panelObject.add(textCustAge);
    panelObject.add(buttonAccept);
    ValidateAction validateButton=new ValidateAction();
    buttonAccept.addActionListener(validateButton);
  }
  class ValidateAction implements ActionListener
  {
     public void actionPerformed(ActionEvent evt)        
     {
          Object obj=evt.getSource();
          if(obj==buttonAccept)
          {
             CustomerAge custObj=new CustomerAge();
            int age=Integer.parseInt(textCustAge.getText());           
          try
             {
                custObj.setAge(age);
                getAppletContext().showStatus("Valid entry!!");
             }
             catch(IllegalAgeException e)
             {
                getAppletContext().showStatus(e.getMessage());
             }
          }
      }
   }
}