Name: eiC57698 Date: 02/09/98



  JPopup menu throws java.io.NotSerializableException on
 com.sun.java.swing.JPopupMenu$MouseGrabber

  Here is test case. Execute it, press down arrow on top combo box to
 activate popup, hide popup, press "Serialize" button.
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/*
 * Experiments with comboBox
 */

import java.awt.*;
import java.awt.event.*;
import java.io.*;
import com.sun.java.swing.*;
import com.sun.java.swing.organic.*;

public class ComboBoxTest extends JFrame implements
ItemListener, ActionListener {
  // The initial width and height of the frame
  public static int WIDTH = 300;
  public static int HEIGHT = 300;
  
  Button serializeButton=null;
  JComboBox days;

  public ComboBoxTest(String lab) {
    super(lab);
    
    // create each button
    days = new JComboBox( );
    days.addItem( "Sunday" );
    days.addItem( "Monday" );
    days.addItem( "Tuesday");
    days.addItem( "Wednesday");
    days.addItem( "Thursday");
    days.addItem( "Friday");
    days.addItem( "Saturday" );
    days.addItemListener( this );
    days.addActionListener( this );

    JComboBox months = new JComboBox();
    months.addItem( "Jan" );
    months.addItem( "Feb" );
    months.addItem( "Mar" );
    months.addItem( "Apr" );
    months.addItem( "May" );
    months.addItem( "Jun" );
    months.addItem( "Jul" );
    months.addItem( "Aug" );
    months.addItem( "Sep" );
    months.addItem( "Oct" );
    months.addItem( "Nov" );
    months.addItem( "Dec" );

    // Add to buttons for serialization/deserialization
    serializeButton = new Button( "Serialize" );
    serializeButton.addActionListener( this );
    
    // Get contents area
    Container content = getContentPane();
    // Set layout to GridLayout - 2 rows x 1 column
    content.setLayout( new GridLayout( 4, 1 ));
    // add to screen
    content.add( days );
    content.add( serializeButton );
    content.add( months );
  }

  public static void main (String args[]) {
    ComboBoxTest frame = new ComboBoxTest("First Swing Stuff");

    frame.addWindowListener(new WindowAdapter() {
      public void windowClosing(WindowEvent e) {System.exit(0);}
      public void mouseExited( WindowEvent e ) { System.out.println( "Mouse ex" );}
    });

    frame.setSize(WIDTH, HEIGHT);
    frame.setVisible(true);
  }

  public void actionPerformed( ActionEvent e ) {
    System.out.println( "actionPerformed " + e.getActionCommand());
    Object obj=e.getSource();
    if ( obj instanceof Button ) {
      String lab=e.getActionCommand();
      if ( lab.equals( "Serialize") ) {
System.out.println( "Serialization of ComboBoxes" );
try {
FileOutputStream f =
new FileOutputStream( "ComboBoxTestComboBoxes.ser" );
ObjectOutput s = new ObjectOutputStream( f );
s.writeObject( "Days combobox" );
s.writeObject( days );
s.flush();
} catch ( Exception exc ) {
System.err.println( "An exception occured while serialize days" +
exc.getMessage());
exc.printStackTrace();
}
      }
    }
  }

  public void itemStateChanged( ItemEvent e ) {
    System.out.println( "itemState " + e.getItem() );
  }
}
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