Shortening method based on an argument name

As you can see below, I have a method which executes statements based on the first letter of a component firing an ItemEvent:

public void itemStateChanged(ItemEvent ie) {
    if(ie.getSource() == rRadioButton) {
        currentScale = "r";
        ((DefaultEditor) rSpinner.getEditor()).getTextField().requestFocus();
    }
    else if(ie.getSource() == gRadioButton) {
        currentScale = "g";
        ((DefaultEditor) gSpinner.getEditor()).getTextField().requestFocus();
    }
    else if(ie.getSource() == bRadioButton) {
        currentScale = "b";
        ((DefaultEditor) bSpinner.getEditor()).getTextField().requestFocus();
    }
    //...
}

Is it possible to easily shorten the method and make it more automatic?

If the argument was an ActionEvent I could use getActionCommand to assign the value for currentScale but the same number of lines of code would be needed first to setActionCommand for every component.

I could also use setName and getName for components but this will result it the same issue as described above.

Also it would be good to be able to automatically point to a specific Spinner based on a specific RadioButton as you can see in the attached source code.

Maybe there is a possibility to use reflection for this but I don't know if this could work.

Without seeing the greater context in which this code appears such as how the components are constructed, and not having kept up with Spring since 1999, I can only address the immediate code. The above could be converted to use two maps: one for the text fields and another for the currentScale strings.

In the code that builds the components, create the two maps and store them in instance fields of the same class.

private final Map textFieldsByRadioButton = new IdentityHashMap<>();
private final Map scalesByRadioButton = new IdentityHashMap<>();

private void buildComponents() {
    ...
    addRadioButtonSpinnerMapping(rRadioButton, rSpinner, "r");
    addRadioButtonSpinnerMapping(gRadioButton, gSpinner, "g");
    addRadioButtonSpinnerMapping(bRadioButton, bSpinner, "b");
}

private void addRadioButtonSpinnerMapping(JRadioButton button, JSpinner spinner, String scale) {
    textFieldsByRadioButton.put(button, ((DefaultEditor) spinner.getEditor()).getTextField());
    scalesByRadioButton.put(button, scale);
}

public void itemStateChanged(ItemEvent ie) {
    Object source = ie.getSource();
    JTextField textField = textFieldsByRadioButton.get(source);
    if (textField != null) {
        currentScale = scalesByRadioButton.get(source);
        textField.requestFocus();
    }
    ...
}

While it requires slightly more code, it only takes one line to add another spinner.

StackExchange Code Review Q#23398, answer score: 2