文件下载

springMVC文件下载

目录结构

这里我用的是maven

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">

  <!--listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
  </listener>-->

  <servlet>
    <servlet-name>dispatcherServlet</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <!-- <load-on-startup>1</load-on-startup>是启动顺序，让这个Servlet随Servletp容器一起启动 -->
    <!-- <load-on-startup>1</load-on-startup>-->
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>classpath:springmvc-config.xml</param-value>
    </init-param>
  </servlet>

  <servlet-mapping>
    <servlet-name>dispatcherServlet</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>

  <!-- 配置过滤器, 设置编码为UTF-8 -->
  <filter>
    <filter-name>CharacterFilter</filter-name>
    <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
    <init-param>
      <param-name>encoding</param-name>
      <param-value>UTF-8</param-value>
    </init-param>
  </filter>
  <filter-mapping>
    <filter-name>CharacterFilter</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>

</web-app>

springmvc-config.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:p="http://www.springframework.org/schema/p"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xmlns:jee="http://www.springframework.org/schema/jee"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xsi:schemaLocation="
        http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.1.xsd
        http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.0.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd
        http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-4.0.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd">

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


    <mvc:default-servlet-handler/>
    <!-- 注释配置 -->
    <mvc:annotation-driven/>

    <!-- 配置视图解析器 -->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/views/"/>
        <property name="suffix" value=".jsp"/>
    </bean>

</beans>

TestResponseEntity.java

package com.test;

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 javax.servlet.ServletContext;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.io.InputStream;

@Controller
public class TestResponseEntity {

    @RequestMapping("/testResponseEntity")
    public ResponseEntity<byte[]> testResponseEntity(HttpSession session) throws IOException {
        byte[] body = null;
        ServletContext servletContext = session.getServletContext();
        InputStream in = servletContext.getResourceAsStream("/file/hibernate_maven.txt");
        body = new byte[in.available()];
        in.read(body);
        HttpHeaders headers = new HttpHeaders();
        headers.add("Content-Disposition","attachment;filename=hibernate_maven.txt");
        HttpStatus statusCode = HttpStatus.OK;

        ResponseEntity<byte[]> response = new ResponseEntity<byte[]>(body,headers,statusCode);

        return response;
    }

}

index.jsp

<%--
  Created by IntelliJ IDEA.
  User: Administrator
  Date: 2019/9/3
  Time: 17:04
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>
<a href="testResponseEntity">下载文件</a>
</body>
</html>

运行