excepttest.java

core java

/**
 * @version 1.20 06 May 1998
 * @author Cay Horstmann
 */

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

public class ExceptTest extends JFrame
   implements ActionListener
{  public ExceptTest()
   {  JPanel p = new JPanel();;
      ButtonGroup g = new ButtonGroup();
      p.setLayout(new GridLayout(8, 1));
      divideByZeroButton 
         = addRadioButton("Divide by zero", g, p);
      badCastButton = addRadioButton("Bad cast", g, p);    
      arrayBoundsButton 
         = addRadioButton("Array bounds", g, p);    
      nullPointerButton 
         = addRadioButton("Null pointer", g, p);    
      negSqrtButton = addRadioButton("sqrt(-1)", g, p);    
      overflowButton = addRadioButton("Overflow", g, p);    
      noSuchFileButton 
         = addRadioButton("No such file", g, p);    
      throwUnknownButton 
         = addRadioButton("Throw unknown", g, p);    
      getContentPane().add(p);
   }

   private JRadioButton
      addRadioButton(String s, ButtonGroup g, JPanel p)
   {  JRadioButton button = new JRadioButton(s, false);
      button.addActionListener(this);
      g.add(button);
      p.add(button);
      return button;
   }

   public void actionPerformed(ActionEvent evt) 
   {  try
      {  Object source = evt.getSource();
         if (source == divideByZeroButton)
         {  a[1] = a[2] / (a[3] - a[3]);
         }
         else if (source == badCastButton)
         {  f = (Frame)evt.getSource();
         }
         else if (source == arrayBoundsButton)
         {  a[1] = a[10];
         }
         else if (source == nullPointerButton)
         {  f = null;
            f.setSize(200, 200);            
         }
         else if (source == negSqrtButton)
         {  a[1] = Math.sqrt(-1);
         }
         else if (source == overflowButton)
         {  a[1] = 1000 * 1000 * 1000 * 1000;
            int n = (int)a[1];
         }
         else if (source == noSuchFileButton)
         {  FileInputStream is 
               = new FileInputStream("No such file");
         }
         else if (source == throwUnknownButton)
         {  throw new UnknownError();
         }
      }
      catch(RuntimeException e)
      {  System.out.println("Caught RuntimeException: " + e);
      }
      catch(Exception e)
      {  System.out.println("Caught Exception: " + e);
      }
   }

   public static void main(String[] args)
   {  JFrame frame = new ExceptTest();
      frame.setSize(150, 200);
      frame.addWindowListener(new WindowAdapter() 
         {  public void windowClosing(WindowEvent e) 
            { System.exit(0); } 
         } );

      frame.show();  
   }
   
   private double[] a = new double[10];
   private Frame f = null;
   private JRadioButton divideByZeroButton;
   private JRadioButton badCastButton; 
   private JRadioButton arrayBoundsButton; 
   private JRadioButton nullPointerButton; 
   private JRadioButton negSqrtButton; 
   private JRadioButton overflowButton; 
   private JRadioButton noSuchFileButton; 
   private JRadioButton throwUnknownButton; 
}