code: public static String makeGUID() {
          String uuid = "";
          String chars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
          int rnd = 0;
          int r;
  
          for (int i = 0; i < GUID_STRING_LENGTH; i += 1) {
              if (i == 8 || i == 13 ||  i == 18 || i == 23) {
                  uuid = uuid + "-";
              } else if (i == 14) {
                  uuid = uuid + "4";
              } else {
                  if (rnd <= 0x02) {
                      rnd = (int) (0x2000000 + Math.round(java.lang.Math.random() * 0x1000000));
                  }
                  r = rnd & 0xf;
                  rnd = rnd >> 4;
  
                  if (i == 19) {
                      uuid = uuid + chars.charAt((r & 0x3) | 0x8);
                  } else {
                      uuid = uuid + chars.charAt(r);
                  }
              }
          }
          return uuid;
      }
docs: Create a globally unique identifier for naming instances
  
  @return New globally unique identifier