@Override
    public void deserializeHeader(InvokeContext invokeContext) throws DeserializationException {
        if (this.getHeader() != null && this.getRequestHeader() == null) {
            if (this.getCustomSerializer() != null) {
                try {
                    this.getCustomSerializer().deserializeHeader(this);
                } catch (DeserializationException e) {
                    throw e;
                } catch (Exception e) {
                    throw new DeserializationException(
                        "Exception caught when deserialize header of rpc request command!", e);
                }
            }
        }
    }
create request command with id and request object
@param request request object
src/main/java/com/alipay/remoting/rpc/protocol/RpcRequestCommand.java