assertTrue( getBackupFile(f).exists() );
System.out.println("Memento after backup: "
+ getBackupFile(f).getPath());
// rollback
m.rollback();
// ensures that the original file exists
assertTrue( f.exists() );
assertFalse( getBackupFile(f).exists() );
System.out.println("Memento after rollback: " + f.getPath());