Any idea how to add a JRadioButton.?

[AAlex]

The following code produces this error:
Test.java:2586: Incompatible type for method. Can't convert javax.swing.
ButtonGroup to java.awt.Component.
PanelGroup.add(group);
^
1 error

This is the code:
JPanel PanelGroup = JPanel();
ButtonGroup group = new ButtonGroup();

group.add(oneRadio);
group.add(twoRadio);
group.add(threeRadio);
group.add(fourRadio);

Thanks for your help.