页面跳转的两种方式：转发和重定向-蒲公英云

页面跳转的两种方式：转发和重定向

小鱼儿 2021-12-11 11:53 395阅读 0赞

理论参考https://blog.csdn.net/xybelieve1990/article/details/49486751这篇文章

1 Servlet、location和状态吗302一起完成重定向

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
 * 和location和302一起完成重定向
 * @author Administrator
 *
 */
public class ServletDmo1 extends HttpServlet {
    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        // 向页面输出内容
        response.setContentType("text/html;charset=UTF-8");
        // response.getWriter().write("向班长借钱...");
        // 班长没钱
        response.setStatus(302);
        // 班长告诉我副班长的地址（重定向都是客户端的，带项目名）
        response.setHeader("location", "/day09/1.html");
    }
    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        doGet(request, response);
    }
}

项目day09/1.html

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
    <h3>1.html的相对路径</h3>
    <a href="./demo5">demo5</a>
    <a href="demo5">demo5</a>
    <h3>1.html的绝对路径</h3>
    <a href="http://localhost/day09/demo5">demo5</a>
    <a href="/day09/demo5">demo5</a>
</body>
</html>

demo5是通过配web.xml置文件与反射技术跳转到ServletDemo5

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
 * 配置servlet启动时加载
 * @author Administrator
 *
 */
public class ServletDemo5 extends HttpServlet {
    /**
     * 默认的情况下第一次访问的时候init被调用。
     * 
     */
    public void init() throws ServletException {
        System.out.println("init...");
        // 初始化数据库的链接
    }
    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        // 写的内容
        // 获取表单输入的内容
        // 自己逻辑，通过名称查询数据库，把张三的姓名查到了
        // 把张三返回浏览器,
        //向控制台输出结果
        System.out.println("doGet...");
        // 向页面输出内容
        response.getWriter().write("hello demo5...");
    }
    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        doGet(request,response);
    }
}

2 页面的定时跳转

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
 * 页面定时跳转
 * @author Administrator
 *
 */
public class RefreshServlet extends HttpServlet {
    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        response.getWriter().write("访问到了...");
        // 页面5秒会跳转到ServletDmo1
        response.setHeader("refresh", "5;url=/day09/1.html");
    }
    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        doGet(request, response);
    }
}