public T decode(ProtoHead head, InputStream in, Charset charset) throws IOException {
        this.head = head;
        return decodeContent(in, charset);
    }
public T decode ( ProtoHead head , InputStream in , Charset charset ) throws IOException { this . head = head ; return decodeContent ( in , charset ) ; }
解析反馈结果,head已经被解析过

@param head
@param in
@param charset
@return
@throws IOException