// register an alternative face to this command
CommandFaceDescriptor face = new CommandFaceDescriptor();
command.setFaceDescriptor(ALTERNATE_ID, face);
// and get us a button with that face
AbstractButton otherFacedButton = command.createButton(ALTERNATE_ID);
// test this newly faced dude
command.setEnabled(false);
assertFalse("alternative face button didn't follow up on the command's disabling", otherFacedButton
.isEnabled());