JSpinner does not work for Numbers

[ulvi ugur]

Hi,

Can you please have a look at the following code to figure out why my customer JSpinner throws a runtime "java.lang.ClassCastException: java.math.BigDecimal cannot be cast to java.lang.Integer" error ?

import java.awt.*;
import java.math.BigDecimal;
import java.text.NumberFormat;
import java.text.DecimalFormat;
import java.text.SimpleDateFormat;

import javax.swing.*;
import javax.swing.text.DateFormatter;
import javax.swing.text.DefaultFormatterFactory;
import javax.swing.text.NumberFormatter;

public class MyNumberSpinner extends JSpinner {
    SpinnerModel model = null;
    JComponent editor = null;

    public void initialize(BigDecimal initialValue, int dps) {
        double precision = Math.pow(10, dps);
        double stepSize = 1.0 / precision;
        model = new SpinnerNumberModel(initialValue, 0, 1000000.0, stepSize);
        StringBuffer bf = new StringBuffer("####0.");
        for (int i=0; i<dps;i++) {
            bf.append("#");
        }
        
        NumberFormatter fm = new NumberFormatter(new DecimalFormat("bf"));
        JFormattedTextField txt = new JFormattedTextField(fm);

        this.setModel(model);
        this.setEditor(txt);
    }
    public static void main(String[] args) {
        Frame test = new Frame("TEST");
        test.setSize(200, 100);
        test.setLayout(new BorderLayout());

        MyNumberSpinner tmp = new MyNumberSpinner();

        tmp.initialize(new BigDecimal(12.475), 3);

        JPanel conten = new JPanel();
        conten.add(tmp);

        test.add(conten, BorderLayout.CENTER);
        test.setVisible(true);

    }
}


Thanks in advance,

Ulvi
  

>

[Ernest Friedman-Hill]

The Javadoc for the SpinnerNumberModel constructor you're calling says

All of the parameters must be mutually Comparable, value and stepSize must be instances of Integer Long, Float, or Double.

[Rob Spoor]

You'll need to create your own version of SpinnerNumberModel. Fortunately the source is available in the src.zip file inside your JDK folder.

[ulvi ugur]

Hi Guys,

I tried Ernest's path and used the constructor with Comparables but this time it started throwing casting exceptions about Byte and BigInteger which told me that I have to go either in the src from JDK or do my own stuff.

Thanks Rob, that was a good advice, generating another class for this feels a bit of an overkill but totally made sense compared to this "casting chaos".

Thanks and cheers,

Ulvi