How to add to an an already existing textfile

I'm using PrintWriter with BufferedWriter to write to a file. But each time the I write to a file and close it, it deletes everything that was already in there and adds the new text i just had written. Is there a way not to delete the already existing text and just start adding text to the next line?

[309 byte] By [blackmagea] at [2007-11-27 5:36:15]