JComboBox QUESTION - Listener Methods.

Question

Dear Everyone,
At the moment I am working on a UI that utilises four JComboboxes. Each of the four JComboboxes contains an index of 10 numeric values, namely 0 - 9. I intend on using the concatenated values of all four boxes to represent a four digit year value, e.g.: 1583, 1902, 2050, 9504, etc.
I need to write some code that listens to each of the four JComboboxes and places the user selected number (from the JComboboxes index) into a variable.
Once the values of all four JComboboxes are held in four variables I then need to concatenate the variables so that they represent a single year, e.g.: 1583.
Once I have the concatenated value I will then perform relative mathematical operations.
If anybody has any suggestions as to how I can listen to the JComboboxes and then place the selected index values into variables they will be greatly appreciated.
Thanks

Answer 1

How about this:
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import java.util.*;
public class Jconbo extends JFrame
     Vector v       = new Vector();
     JComboBox jc1  = new     JComboBox(v);
     JComboBox jc2  = new     JComboBox(v);
     JComboBox jc3  = new     JComboBox(v);
     JComboBox jc4  = new     JComboBox(v);
     int       year = 0;
public Jconbo()
     addWindowListener(new WindowAdapter()
    {     public void windowClosing(WindowEvent ev)
          {     dispose();
               System.exit(0);}});
     for (int j=0; j < 10; j++) v.add(""+j);     
       setBounds(1,1,500,300);
     addJc(jc1);
     addJc(jc2);
     addJc(jc3);
     addJc(jc4);
     getContentPane().setLayout(new FlowLayout());
     setVisible(true);
private void addJc(final JComboBox jc)
     getContentPane().add(jc);
     jc.setPreferredSize(new Dimension(100,24));
     jc.setSelectedIndex(0);
     jc.addItemListener( new ItemListener()
     {     public void itemStateChanged(ItemEvent e)
               year = jc1.getSelectedIndex() * 1000 +
                       jc2.getSelectedIndex() * 100 +
                       jc3.getSelectedIndex() * 10 +
                       jc4.getSelectedIndex();           
               System.out.println(""+year);
public static void main (String[] args) 
     new Jconbo();
Noah
unformatted
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import java.util.*;
public class Jconbo extends JFrame
     Vector v = new Vector();
     JComboBox jc1 = new     JComboBox(v);
     JComboBox jc2 = new     JComboBox(v);
     JComboBox jc3 = new     JComboBox(v);
     JComboBox jc4 = new     JComboBox(v);
     int year = 0;
public Jconbo()
     addWindowListener(new WindowAdapter()
{     public void windowClosing(WindowEvent ev)
          {     dispose();
               System.exit(0);}});
     for (int j=0; j < 10; j++) v.add(""+j);     
     setBounds(1,1,500,300);
     addJc(jc1);
     addJc(jc2);
     addJc(jc3);
     addJc(jc4);
     getContentPane().setLayout(new FlowLayout());
     setVisible(true);
private void addJc(final JComboBox jc)
     getContentPane().add(jc);
     jc.setPreferredSize(new Dimension(100,24));
     jc.setSelectedIndex(0);
     jc.addItemListener( new ItemListener()
     {     public void itemStateChanged(ItemEvent e)
               year = jc1.getSelectedIndex() * 1000 +
                    jc2.getSelectedIndex() * 100 +
                    jc3.getSelectedIndex() * 10 +
                    jc4.getSelectedIndex();           
               System.out.println(""+year);
public static void main (String[] args)
     new Jconbo();
}