Of files and filepaths in Java

This is a major stumbling block for me every time. As I learn new methods I will keep updating .

For now here is the simplest :

FileReader f = new FileReader("tmp.txt");

Now where the hell do u place tmp.txt, you might ask. Well, to find where Java tries to look for tmp.txt, do this

System.out.println(System.getProperty("user.dir");

To open a file relative to the class file location is something that would really help. And it is supposed to work by using class.getClassLoader().getResourceAsStream(), but it didnt work for me, will post as soon as I know how it works.