RequestUtils

Returns remote ip address.

• First,it lookup request header("x-forwarded-for"->"Proxy-Client-IP"->"WL-Proxy-Client-IP")

• Second,invoke request.getRemoteAddr()

Return the true servlet path. When servletPath provided by container is empty,It will return requestURI-contextpath'

查找当前调用的action对应的.do
例如http://localhost/myapp/dd.do 返回/dd.do
http://localhost/myapp/dir/to/dd.do 返回/dir/to/dd.do

Return Useragent of request.

Set Content-Disposition header