How to retreive raw post data from HttpServletRequest in java

public static String getPostData(HttpServletRequest req) {
StringBuilder sb = new StringBuilder();
try {
BufferedReader reader = req.getReader();
reader.mark(10000);

String line;
do {
line = reader.readLine();
sb.append(line).append("\n");
} while (line != null);
reader.reset();
// do NOT close the reader here, or you won't be able to get the post data twice
} catch(IOException e) {
logger.warn("getPostData couldn't.. get the post data", e);  // This has happened if the request's reader is closed
}

return sb.toString();
}