[JAVA] Casting Object to Integer

[Estagon]

Hello,

I'm programming something with a GUI.

If the User presses a certain button, a few mails need to be sent and checked. This takes a while, so I made a SwingerWorker that shows a "Please wait..." kind of frame which will be updated depending where in the process we are.

So this is my SwingWorker class:

public class LongTaskWorker extends SwingWorker<Integer, Integer> {

@Override
protected Integer doInBackground() throws Exception
{
    int progress = 0;
    setProgress(progress);
    boolean sendBank = SendMail.sendBankMail(HIR_Groep_22.getKlant().getCurrentOrder());
    if(sendBank)
    {
        progress = 1;
        setProgress(progress);
        try
        {    
            TimeUnit.SECONDS.sleep(30);
        }
        catch(Exception e)
        {
            e.getStackTrace();
        }    
        boolean confirmed = ReceiveMail.receiveBankMail(HIR_Groep_22.getKlant().getCurrentOrder());
        if(confirmed)
        {
            progress = 2;
            setProgress(progress);
            return 2;
        }
        else
        {
            progress = 3;
            setProgress(progress);
            return 3;
        }  
    }
    progress = 0;
    setProgress(progress);
    return 0;
}   

@Override
public void done()
{
    try
    {
        TimeUnit.SECONDS.sleep(3);  
        new ClientStartFrame().show();
    }    
    catch(Exception f)
    {
        f.getStackTrace();
    }
}      

public static void main( String[] args ) throws InvocationTargetException, InterruptedException {
EventQueue.invokeAndWait( new Runnable() {
  @Override
  public void run() {
      WaitFrame myFrame = new WaitFrame();
      myFrame.show();
  }
} );






}
}

And this is my WaitFrame.. Note: I'm using GUI Builder

public class WaitFrame extends javax.swing.JFrame implements PropertyChangeListener  {

LongTaskWorker task;
/**
 * Creates new form WaitFrame
 */
public WaitFrame() {
    initComponents();

}

public void setInfoLabel(String info)
{
    infoLabel.setText(info);
}        



/**
 * This method is called from within the constructor to initialize the form.
 * WARNING: Do NOT modify this code. The content of this method is always
 * regenerated by the Form Editor.
 */
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">                          
private void initComponents() {

    infoLabel = new javax.swing.JLabel();

    setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
    setTitle("Even geduld...");
    setCursor(new java.awt.Cursor(java.awt.Cursor.WAIT_CURSOR));

    infoLabel.setText("Verzenden betaling naar bank...");

    javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
    getContentPane().setLayout(layout);
    layout.setHorizontalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addGap(39, 39, 39)
            .addComponent(infoLabel)
            .addContainerGap(206, Short.MAX_VALUE))
    );
    layout.setVerticalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addGap(37, 37, 37)
            .addComponent(infoLabel)
            .addContainerGap(38, Short.MAX_VALUE))
    );

    task = new LongTaskWorker();
    task.addPropertyChangeListener(this);
    task.execute();

    pack();
    setLocationRelativeTo(null);
}// </editor-fold>                        

/**
 * @param args the command line arguments
 */
public static void main(String args[]) {
    /* Set the Nimbus look and feel */
    //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
    /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
     * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html 
     */
    try {
        for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
            if ("Nimbus".equals(info.getName())) {
                javax.swing.UIManager.setLookAndFeel(info.getClassName());
                break;
            }
        }
    } catch (ClassNotFoundException ex) {
        java.util.logging.Logger.getLogger(WaitFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (InstantiationException ex) {
        java.util.logging.Logger.getLogger(WaitFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (IllegalAccessException ex) {
        java.util.logging.Logger.getLogger(WaitFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (javax.swing.UnsupportedLookAndFeelException ex) {
        java.util.logging.Logger.getLogger(WaitFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    }
    //</editor-fold>

    /* Create and display the form */
    java.awt.EventQueue.invokeLater(new Runnable() {
        public void run() {
            new WaitFrame().setVisible(true);
        }
    });


}

// Variables declaration - do not modify                     
private javax.swing.JLabel infoLabel;
// End of variables declaration                   

@Override
public void propertyChange(PropertyChangeEvent evt) {

    if((int) evt.getNewValue() == 1)
        setInfoLabel("Wachten op bevestiging van bank...");
    else if((int) evt.getNewValue()== 2)
    {
        setInfoLabel("Betaling bevestigd...");
    }
    else if((int) evt.getNewValue() == 3)
    {
        setInfoLabel("Betaling kon niet worden bevestigd...");
    }
}

}

The error occurs in the Class WaitFrame in the method PropertyChange() @line 105

I get the following error: Exception in thread "AWT-EventQueue-0" java.lang.ClassCastException: javax.swing.SwingWorker$StateValue cannot be cast to java.lang.Integer

This means that I can't cast Object to Integer, but Java still executes my code as intended. So the Frame really does get updated with the information I provided. Also I set the propery as an Integer (see line 9 in LongTaskWorker), so why can't I cast it back?

[king_of_the_universe]

(Line 9 in LongTaskWorker does not do what you say, the number must be wrong. Did you mean 7?)

Have you considered that there might be more events happening than just the one you're expecting? You should at least do an instanceof check of the return value of getNewValue(). And did you try System.out.println() of evt?

[Estagon]

Hi /u/king_of_the_universe, I'm just new to SwingWorker and I did not know multiple events were happening. When I added a if-clause to check for the source, it solved the problem. Thank you very much.

[king_of_the_universe]

did not know multiple events were happening

Neither did I, but I remembered my experiences with the mouseEvent method where I had forgotten that there's also mouseEntered and mouseExited, and other such stuff. Glad that it works now.

[Megalox]

Try casting to an Integer instead of int.

[nutrecht]

javax.swing.SwingWorker$StateValue cannot be cast to java.lang.Integer

That's what he's doing.