SSM笔记-SpringMVC的上传和下载

1、上传
特别需要的jar：commons-fileupload-1.3.3.jar和commons-io-2.6.jar
步骤：
①配置mvc:annotation-driven
②配置multipartResolver
③创建html页面
④创建handler

2、下载
①创建handler,方法返回值为ResponseEntity类型
②设置ResponseEntity的内容、请求头、请求状态
③把设置好的ResponseEntity对象写到返回给页面即可

3、注意事项
①要在web.xml配置HiddenHttpMethodFilter
②要在springmvc配置文件配置MultipartResolver
③提交页面的form里面需要配置enctype=”multipart/form-data”

4、web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" version="3.1">
  <display-name>SpringMVC_10_UpDownload</display-name>
  <servlet>
    <servlet-name>springDispatcherServlet</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>classpath:springmvc.xml</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
  </servlet>
  <servlet-mapping>
    <servlet-name>springDispatcherServlet</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>
  <filter>
    <filter-name>HiddenHttpMethodFilter</filter-name>
    <filter-class>org.springframework.web.filter.HiddenHttpMethodFilter</filter-class>
  </filter>
  <filter-mapping>
    <filter-name>HiddenHttpMethodFilter</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>
</web-app>

5、springmvc.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context"
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.3.xsd
        http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.3.xsd">

    <!-- 配置自动扫描包 -->
    <context:component-scan base-package="com.test.springmvc"></context:component-scan>

    <!-- 配置视图解析器,把handler返回值解析为实际视图 -->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/"></property>
        <property name="suffix" value=".jsp"></property>
    </bean>

    <mvc:annotation-driven></mvc:annotation-driven>

    <!-- 配置MultipartResolver -->
    <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
        <property name="defaultEncoding" value="UTF-8"></property>
    </bean>

</beans>

6、Handler.java

package com.test.springmvc.handlers;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;

import javax.servlet.ServletContext;
import javax.servlet.http.HttpSession;

import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.multipart.MultipartFile;

@Controller
public class Handler {

    @RequestMapping("/testUpload")
    public String testUpload(@RequestParam(value="desc",required=false)String desc, @RequestParam("file")MultipartFile file){
        System.out.println(desc);
        if(file!=null){
            BufferedReader in = null;
            BufferedWriter bw = null;
            try{
                String path = "E:/workspace/SpringMVC_10_UpDownload/WebContent/files/";
                System.out.println(file.getOriginalFilename());
                in = new BufferedReader(new InputStreamReader(file.getInputStream()));
                StringBuffer buffer = new StringBuffer();
                String line = "";
                while ((line = in.readLine()) != null){
                   buffer.append(line);
                }
                String filestr = buffer.toString();
                System.out.println(filestr);
                bw = new BufferedWriter(new FileWriter(path+"new"+file.getOriginalFilename(), true));
                bw.write(filestr);
                bw.newLine();
                bw.flush();
                return "redirect:/result?status=success";
            }catch(Exception e){
                e.getMessage();
                try {
                    bw.close();
                    in.close();
                } catch (IOException e1) {
                    e1.printStackTrace();
                }
                return "redirect:/result?status=fail";
            }
        }else{
            return "redirect:/result?status=fail";
        }
    }
    @RequestMapping("/result")
    public String toResult(){
        return "result";
    }

    @RequestMapping("/testDownload")
    public ResponseEntity<byte[]> testDownload(HttpSession session) throws IOException{
        byte[] body = null;
        String context = "sdfasdjkahsjdkfhalksdjhfajklhjh";
        ServletContext servletContext = session.getServletContext();
        body = context.getBytes();
        HttpHeaders headers = new HttpHeaders();
        headers.add("Content-Disposition", "attachment;filename=test.txt");
        HttpStatus status = HttpStatus.OK;
        ResponseEntity<byte[]> responseEntity = new ResponseEntity<byte[]>(body,headers,status);
        return responseEntity;
    }
}

7、index.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!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>

    <form action="testUpload" method="POST" enctype="multipart/form-data">
        File:<input type="file" name="file">
        Desc:<input type="text" name="desc">
        <input type="submit" value="submit">
    </form>
    <br><br>
    <a href="testDownload" id="testDownload">testDownload</a>
    <br><br>

    1、上传<br>
    特别需要的jar：commons-fileupload-1.3.3.jar和commons-io-2.6.jar<br>
    步骤：<br>
    ①配置mvc:annotation-driven<br>
    ②配置multipartResolver<br>
    ③创建html页面<br>
    ④创建handler<br>
    2、下载<br>
    ①创建handler,方法返回值为ResponseEntity类型<br>
    ②设置ResponseEntity的内容、请求头、请求状态<br>
    ③把设置好的ResponseEntity对象写到返回给页面即可<br>
</body>
</html>

8、result.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!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>
RESULT >> <%=request.getParameter("status") %>
</body>
</html>

9、项目目录

10、demo
https://download.csdn.net/download/qq_22778717/10601174