Recently I had a problem that I needed to send some text from Android over webview to JavaScript, but with new lines included, problem was that webview didn't respect \r\n.
This is my solution:
...
receivedPacket = new DatagramPacket(buf, buf.length);
...
final String strReceivedPacket = new String(receivedPacket.getData(), 0, receivedPacket.getLength()).replaceAll("\r\n", "\\\\r\\\\n");