public static void hexdump (String s) {

         byte[] data = null;
         try { data = s.getBytes("us-ascii"); } catch (Exception x) { }

         String h = "", t = "";
         int c = 16;
         for (byte b : data) {
             h += String.format("%02x ", b);
             t += (b < 32 ? "." : String.format("%c", b));
             if (-- c == 0) {
                 System.out.printf(": %-48s  %-16s\n", h, t);
                 c = 16;
                 h = t = "";
             }
         }
         if (c < 16)
             System.out.printf(": %-48s  %-16s\n", h, t);

     }