ActionListeners on JRadioButtons don't get notified when selection is changed 
with arrow keys. If radio buttons are part of a button group, using the arrow keys to select a 
radio button does not fire action listeners.
See this closed bug: https://bugs.openjdk.java.net/browse/JDK-6314014 
To reproduce this, run the RadioButtonDemo: 
https://docs.oracle.com/javase/tutorial/uiswing/examples/zipfiles/components-RadioButtonDemoProject.zip 
Use the up and down arrows to change the selection.  Note that the selection 
appears to change, but the picture doesn't change until the space bar is   
pressed. 
Arrows should either just change the focus without changing  the selection, 
or the selection should fire action listeners.