request是JSP技术中中的一个常用API，继承自import javax.servlet.http.HttpServletRequest;

下面通过一个例子来看看request都能取出哪些值：

package cn.edu.Request;import java.io.IOException;import java.io.PrintWriter;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;public class RequestDemo1 extends HttpServlet {	public void doGet(HttpServletRequest request, HttpServletResponse response)			throws ServletException, IOException {       System.out.println(request.getRequestURI());       System.out.println(request.getRequestURL());              System.out.println(request.getQueryString());//返回参数信息（URL中带参）              System.out.println(request.getRemoteAddr());//拿到来访者的IP地址       System.out.println(request.getRemoteHost());//拿到来访者的完整主机名              System.out.println(request.getRemotePort());//拿到来访者所使用的网络端口号              System.out.println(request.getMethod());//拿到客户端的请求方式	}	public void doPost(HttpServletRequest request, HttpServletResponse response)			throws ServletException, IOException {       doGet(request,response);	}}