直接来，ResponseDemo1代码，get请求到post请求，重定向到ResponseDemo2
我的虚拟目录为
ResponseDemo1代码，302是重定向状态码，Http状态码大全
package com.lingaolu.response;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.*;
import java.io.IOException;
/**
* @author 林高禄
* @create 2020-07-10-15:24
*/
@WebServlet("/responseDemo1")
public class ResponseDemo1 extends HttpServlet {
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
System.out.println("responseDemo1进来了......");
// 设置状态码为302
response.setStatus(302);
// 动态获取虚拟目录，以后修改虚拟目录的时候就不用了修改代码
String contextPath = request.getContextPath();
// 设置响应头location
response.setHeader("location",contextPath+"/responseDemo2");
}
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doPost(request,response);
}
}
ResponseDemo2代码
package com.lingaolu.response;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.*;
import java.io.IOException;
/**
* @author 林高禄
* @create 2020-07-10-15:24
*/
@WebServlet("/responseDemo2")
public class ResponseDemo2 extends HttpServlet {
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
System.out.println("responseDemo2进来了......");
}
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doPost(request,response);
}
}
浏览器访问，访问前
浏览器访问，访问后
控制台输出
从以上结果可以看出：
由于状态码固定是302，响应头固定是location，所以请求转发提供了更方便的方式
void sendRedirect(String var1)
ResponseDemo3代码
package com.lingaolu.response;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.*;
import java.io.IOException;
/**
* @author 林高禄
* @create 2020-07-10-15:24
*/
@WebServlet("/responseDemo3")
public class ResponseDemo3 extends HttpServlet {
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
System.out.println("responseDemo3进来了......");;
// 动态获取虚拟目录，以后修改虚拟目录的时候就不用了修改代码
String contextPath = request.getContextPath();
response.sendRedirect(contextPath+"/responseDemo2");
}
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doPost(request,response);
}
}
启动，浏览器访问
控制台输出
我们把ResponseDemo3代码改一下，重定向到百度
package com.lingaolu.response;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.*;
import java.io.IOException;
/**
* @author 林高禄
* @create 2020-07-10-15:24
*/
@WebServlet("/responseDemo3")
public class ResponseDemo3 extends HttpServlet {
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
System.out.println("responseDemo3进来了......");;
response.sendRedirect("http://www.baidu.com");
}
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doPost(request,response);
}
}
重启访问，就重定向到百度了
从上面结果我们可以看出，重定向可以访问其他服务器的资源
我们写一个ResponseDemo4，探索一下共享数据情况，ResponseDemo4里请求写进了一个数据name
package com.lingaolu.response;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.*;
import java.io.IOException;
/**
* @author 林高禄
* @create 2020-07-10-15:24
*/
@WebServlet("/responseDemo4")
public class ResponseDemo4 extends HttpServlet {
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
System.out.println("responseDemo4进来了......");
request.setAttribute("name","林大帅");
String contextPath = request.getContextPath();
response.sendRedirect(contextPath+"/responseDemo2");
}
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doPost(request,response);
}
}
同时ResponseDemo2改一下，获取数据name
重启，浏览器访问
控制台输出：
从上面的null可以看出，重定向不可以共享数据
重定向的特点总结：（与之对应的------请求转发详情与特点）
