code: public static String readStringUTF16(ByteBuffer buffer, int strLen) {
          String str = Buffers.readString(buffer, strLen);
          for (int i = 0; i < str.length(); i++) {
              char c = str.charAt(i);
              if (c == 0) {
                  return str.substring(0, i);
              }
          }
          return str;
      }
docs: read utf-16 encoding str, use zero char to end str.