Host interface httpServletRequest can not get inputStream when using router plugin

[chengyouling]

What happened?

Host interface httpServletRequest can not get inputStream when using router plugin

How can we reproduce it (as minimally and precisely as possible)?

change using getParameterMap method to getQueryString method get url parameters.

Bug is triggered when the following conditions are met：
1.http/https request.
2.POST method.
3.Content-Type is application/x-www-form-urlencoded.
4.call method getParameter method in servlet.

Anything else we need to know?

No response

Sermant version

2.1.0

OS version

No response