HttpServletRequest request 方法调用，参数应该填什么？

普通类里边是 得不到 httprequest 的
至少 应该 继承 HttpServlet
如下
package test;

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 NatServerServlet extends HttpServlet {

/**
* Constructor of the object.
*/
public NatServerServlet() {
super();
}

/**
* Destruction of the servlet.

*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
}

/**
* The doGet method of the servlet.

*
* This method is called when a form has its tag value method equals to get.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request, response);
}

/**
* The doPost method of the servlet.

*
* This method is called when a form has its tag value method equals to post.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {

response.setContentType("text/html");
String ip=this.getIpAddress(request);
PrintWriter out = response.getWriter();
out.println("ip:"+ip);
out.flush();
out.close();
}
public String getIpAddress(HttpServletRequest request) {

String ip = request.getHeader("x-forwarded-for");
if(ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
ip = request.getHeader("Proxy-Client-IP");
}
if(ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
ip = request.getHeader("WL-Proxy-Client-IP");
}
if(ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
ip = request.getRemoteAddr();
}
return ip;
}
/**
* Initialization of the servlet.

*
* @throws ServletException if an error occure
*/
public void init() throws ServletException {
// Put your code here
}

}

应该填HttpServletRequest request这个类型的参数，我所知道的，这种参数要使用web服务器产生的。

后来怎么解决的呢，我新手，不太懂