ServletRequest和HttpServletRequest的联系与区别

HttpServletRequest和ServletRequest都是接口

HttpServletRequest继承自ServletRequest

HttpServletRequest比ServletRequest多了一些针对于Http协议的方法。如getHeader(String name)，getMethod() ，getSession() 等等。

他们对应的实现类：

javax.servlet.ServletRequestWrapper (implements javax.servlet.ServletRequest)

javax.servlet.http.HttpServletRequestWrapper (implements javax.servlet.http.HttpServletRequest)?