JSP第六次课 response对象的作用

response的基本知识
HttpServlet
Web服务器收到客户端的http请求，会针对每一次请求，分别创建一个用于代表请求的request对象、和代表响应的response对象

request和response对象即代表了请求和响应，那我们要获取客户机提交过来的数据，只需要找request对象就可以了，要想客户机输出数据，只需要找response即可。

response只是一个对象名称，HttpServletResponse类

Student xiaoming=new Student(); 类名: Student 对象名:xiaoming

重定向:重新制定访问的方向
作用:用于从一个Servlet去开启另一个Servlet

重定向:
重定向属于浏览器跳转，不是服务器自己跳转超链接是一样的
重定向跳转页面浏览器地址会发生变化
重定向为两次请求
an重定向可以访问不同服务器的页面跳转

package com.Servlet;

import java.awt.image.RescaleOp;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


@WebServlet("/Servlet1")
public class Servlet1 extends HttpServlet {
	private static final long serialVersionUID = 1L;
	
    
    public Servlet1() {
        super();
        // TODO Auto-generated constructor stub
    }

	
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// response  回复  当浏览器根据地址发送请求servlet.servlet
		//使用response对象回复对象
		//设置servlet发送的数据支撑HTML格式
		response.setContentType("text/html");
		//设置发送servlet 浏览html格式 utf-8
		response.setCharacterEncoding("UTF-8");
		
		//response  回复  内容/数据/消息
		String info="hellow world java";
		String info1="你好,倒计时servlet java jsp";
		
		//使用response获得输出
		OutputStream  os =response.getOutputStream();
		os.write(info.getBytes());
		os.write(info1.getBytes());
	
		
	}

	
		
	}

package com.Servlet;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


@WebServlet("/Servlet2")
public class Servlet2 extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
    
    public Servlet2() {
        super();
        // 
    }

	
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		//设置servlet发送的数据支撑HTML格式
		response.setContentType("text/html");
		//设置发送servlet 浏览html格式 utf-8
		response.setCharacterEncoding("UTF-8");
		String info="abc";
		String info1="20软件三班";
		String info2="你好, "
				+ "java jsp"
				+"1111

2111

3111

"
				+"1111

2111

3111

"
				+""
				+"课表"
				+ ""
				+"4"
				+ "4
1 2 3 
2
5 6 7 
"
				+""
				+""
				+"hellow world see you "
				+ "";
		//将数据写出的
		PrintWriter pw=response.getWriter();
		pw.print(info);
		pw.print(info1);
		pw.print(info2);
		
		
		
	}

	
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doGet(request, response);
	}

}

4
1	2	3
2
5	6	7

package com.Servlet;

import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


@WebServlet("/Servlet3")
public class Servlet3 extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
    
    public Servlet3() {
        super();
        // TODO Auto-generated constructor stub
    }

	
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// 使用对象完成图片的下载
		
		//设置servlet发送的数据支撑HTML格式
		response.setContentType("text/html");
				//设置发送servlet 浏览html格式 utf-8
		response.setCharacterEncoding("UTF-8");
		//设置响应头
		response.setHeader("content-disposition", "attachment;filenname=flower.jpg");
		ServletContext sa=getServletContext();
		String path=sa.getRealPath("/imges/yu.png");
		
		InputStream is =new FileInputStream(path);
		byte [] bytes =new byte[1024];
		int count=-1;
		OutputStream os=response.getOutputStream();
		while((count=is.read(bytes))!=-1) {
			os.write(bytes,0,count);
		}
		
		
		//response.getWriter().append("Served at: ").append(request.getContextPath());
	}

	
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doGet(request, response);
	}

}

package com.Servlet;

import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.util.Random;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


@WebServlet("/Servlet6")
public class Servlet4 extends HttpServlet {
	private static final long serialVersionUID = 1L;

	
	public Servlet4() {
		super();

		System.out.println("Servlet4正在运行中");
		// 创建码
	}

	
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// 生成数字，随机数
		//100000 -1000000
		//[0,1]*900000=[0,900000]+100000
		response.setCharacterEncoding("UTF-8");
		response.setContentType("text/html");
		response.setHeader("refresh", "5");
		
		
		//设置要求浏览器 
		
		
		
		int i=(int)(Math.random()*900000+100000);
		int a=(int)(Math.random()*9000+1000);
		int c=(int)(Math.random()*900+100);
		System.out.println("@@@@"+(new Random().nextInt(900000)+100000));
		
		System.out.println(new Random().nextInt(100));
		System.out.println(Math.random());
		
		PrintWriter  pw =response.getWriter();
		pw.print("你的支付宝到账1000万元，需要的码号为:"+i+",打死也不说	 "";");
		pw.print("你的QQ到账1000万元，需要的码号为:
"+c+",打死也不说	 "";");
		pw.print("你的微信到账1000万元，需要的码号为:"+a+",打死也不说");	
		pw.print("你的手机支付宝到账1000万"+i+"");
		
	}
		
	
	protected void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		// TODO Auto-generated method stub
		doGet(request, response);
	}

}

package com.Servlet;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


@WebServlet("/Servlet5")
public class Servlet5 extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
    
    public Servlet5() {
        super();
        // TODO Auto-generated constructor stub
    }

	
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
	//当浏览器访问servlet5时刻，servlet5回复消息访问servlet1
		System.out.println("servlet5回复消息访问servlet1");
		response.sendRedirect("Servlet1");
	}
		

	
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doGet(request, response);
	}

}

package com.Servlet;

import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.util.Random;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


@WebServlet("/Servlet6")
public class Servlet6 extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
    
    public Servlet6() {
        super();
       
        System.out.println("Servlet6正在运行中");
        // 创建码
    }

	
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// 生成数字，随机数
		//100000 -1000000
		//[0,1]*900000=[0,900000]+100000
		response.setCharacterEncoding("UTF-8");
		response.setContentType("text/html");
		response.setHeader("refresh", "5");
		
		
		//设置要求浏览器 
		
		
		
		int i=(int)(Math.random()*900000+100000);
		int a=(int)(Math.random()*9000+1000);
		int c=(int)(Math.random()*900+100);
		System.out.println("@@@@"+(new Random().nextInt(900000)+100000));
		
		System.out.println(new Random().nextInt(100));
		System.out.println(Math.random());
		
		PrintWriter  pw =response.getWriter();
		pw.print("你的支付宝到账1000万元，需要的码号为:"+i+",打死也不说	 "";");
		pw.print("你的QQ到账1000万元，需要的码号为:
"+c+",打死也不说	 "";");
		pw.print("你的微信到账1000万元，需要的码号为:"+a+",打死也不说");	
		pw.print("你的手机支付宝到账1000万"+i+"");
		
		response.sendRedirect("Servlet1");
		 try { Thread.sleep(5000);
		 Connection conn =	Time.time();
		  } catch (Exception e) 
		  { 
			e.printStackTrace();
			
			} 
		
	}

	
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doGet(request, response);
	}

}

package com.Servlet;

import java.sql.Connection;

public class Time {
	public static int time=60*60*60;
	static Connection time() {
		while (time>0) {
			time--;
			try {
				Thread.sleep(1000);
				int hh=time/1/1%1;
				int mm=time/60%1;
				int ss=time%6;
				if(hh==0 &&mm==0 && ss==0) {
					break;
				}
				System.out.println("小时"+hh+"Сʱ"+mm+"分钟"+ss+"秒");
				
			} catch (InterruptedException e) {
				// TODO: handle exception
		}finally {
			System.out.println("正在跳转页面哦 Servlect1");
		}
		}
		return null;
	}

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		time();
	}

}

运行结果

总结：response对象的作用图片，音频，文件的下载对浏览器的访问随机码的获取 servlet的跳转 HttpServlet
HttpRequest的有关方法，获取HTTP请求信息；
HttpRequest的有关方法，获取HTTP请求信息；
// 生成数字，随机数
//100000 -1000000
//[0,1]*900000=[0,900000]+100000
response.setCharacterEncoding("UTF-8");
response.setContentType("text/html");
//设置要求浏览器
response.setHeader("refresh", "10");
//response 重定向重新指定访问方向
从一个servlet 去开启新的servlet
重定向：属于浏览器的跳转.超链接

浏览地址发生改变
重定向为二次请求。
重定向可以访问不同服务器的跳转。

JSP第六次课 response对象的作用

"+i+",打死也不说 "";"); pw.print("你的QQ到账1000万元，需要的码号为:

"+i+",打死也不说 "";"); pw.print("你的QQ到账1000万元，需要的码号为:

Linux相关栏目本月热门文章

"+i+",打死也不说 "
";"); pw.print("你的QQ到账1000万元，需要的码号为:

"+i+",打死也不说 "
";"); pw.print("你的QQ到账1000万元，需要的码号为: