code: public static void encode(Float value, byte[] dst, int dstOffset) {
          if (value == null) {
              encode(0x7fffffff, dst, dstOffset);
          } else {
              encode(value.floatValue(), dst, dstOffset);
          }
      }
docs: Encodes the given Float object into exactly 4 bytes. A non-canonical NaN
  value is used to represent null.
  
  @param value optional Float value to encode
  @param dst destination for encoded bytes
  @param dstOffset offset into destination array