web工程中URL地址的写法

package com.yyz.response;

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;
//web工程中URL地址的写法
public class ResponseDemo extends HttpServlet {

    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        //servletContext,给服务器用，"/"代表web工程
        this.getServletContext().getRealPath("/download/1.gif");
        //forward,给服务器用，"/"代表web工程。
        this.getServletContext().getRequestDispatcher("/register.html");
        //sendRedirct,给浏览器用，"/"代表webapps。
        response.sendRedirect("/test/register.html");
/**
 * 在register.html中要访问ResponseDemo.java,超链接的写法，给浏览器用，"/"代表webapps
 * <a href="/test/servlet/ResponseDemo"></a>
 */
    }

    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

    }

}