New to Java

i'm having problem of getting the path of the parent directory

example:

[HelloWorld]
    |----[file]
    |         |---- PersonalizedMsg.txt
    |----[classes]
              |----HelloWorld.class

what i want to do is get the URL (path) to the files directory...like C:/HelloWorld/files/

iwhat i'm doing now is

String path = HelloWorld.class.getResource("./").getPath();

this will return the C:HelloWorld/classes/

however..i can't seem to go one level up (to the parent directory of [HelloWorld]

i tried with

String path = HelloWorld.class.getResource("../").getPath();

and

String path = HelloWorld.class.getResource("./../").getPath();

to get c:/HelloWorld/
but it return null;

any help would apperciated.