/** Define enum class that will popuplate your combo box */
public enum E_ComboBoxEnum {

Item1("Item 1"),

Item2("Item 2"),

Item3("Item 3");

private final String _displayName;

/** constructor */
E_ComboBoxEnum(final String displayName) {
    _displayName = displayName;
}

/** overrides method toString() in java.lang.Enum class */
public String toString(){
     return _displayName;
}

} // end enum E_ComboBoxEnum

/** whatever class contains the JComboBox object, could be JFrame, JDialog, etc */
public class ComboBoxGUI extends javax.swing.JDialog {

private javax.swing.JComboBox _myComboBox;

public void createComboBox(){

_myComboBox = new javax.swing.JComboBox();
/** model is set to be a new instance of DefaultComboBoxModel. this model
is initialized with an array of all possible values of E_ExpirationDateIntervals */
_myComboBox.setModel(new javax.swing.DefaultComboBoxModel(E_ExpirationDateIntervals.values()));
}

/** the combo box will now display the Strings defined in the E_ComboBoxEnum class, in the order that they were defined. */

/** _myComboBox.getSelectedItem() will return an E_ComboBoxEnum object  (well technically a generic object that can be cast into an E_ComboBoxEnum object) */


} // end class ComboBoxGUI