Android - text formatting for thermal label printer

I have an Android app which prints labels or order slips on a thermal 3" printer. I need to format certain text in bold, underline, reverse b/w, etc. Used [login to view URL], [login to view URL], but not getting any impact. Need help with correct syntax for formatting text. Sample code below: void networkPrint(String ipAdd) { try { Socket sock = new Socket(ipAdd, 9100); PrintWriter oStream = new PrintWriter([login to view URL]()); [login to view URL](0x8); String str="my message"; [login to view URL](str); [login to view URL]("HI,test from Android Device"); [login to view URL]("\n\n\n\n\n"); [login to view URL](); [login to view URL]();