SpringMVC的文件下载及中文编码问题

Bertha 。 2022-05-25 09:48 186阅读 0赞

首先配置web.xml文件

<?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">
      <display-name>fileupload</display-name>
      <welcome-file-list>
        <welcome-file>index.html</welcome-file>
        <welcome-file>index.htm</welcome-file>
        <welcome-file>index.jsp</welcome-file>
        <welcome-file>default.html</welcome-file>
        <welcome-file>default.htm</welcome-file>
        <welcome-file>default.jsp</welcome-file>
      </welcome-file-list>
    
      
        <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>
    </web-app>

配置springmvc.xml文件

<?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:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" 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.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd">
    
    
        
        <mvc:annotation-driven></mvc:annotation-driven>
        
        <context:component-scan base-package="lhc"></context:component-scan>
        
        <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
            <property name="prefix" value="/WEB-INF/jsp/"></property>
            <property name="suffix" value=".jsp"></property>
        </bean>
    
    </beans>

写一个JSP页面

<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%>
    <%@ page import="java.net.URLEncoder" %>
    <!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>
    <a href="${pageContext.request.contextPath }/download?filename=<%=URLEncoder.encode("风景.jpg","UTF-8")%>">图片下载</a>
    </body>
    </html>

写一个Controller,重点是处理中文编码问题

package lhc.controller;
    
    import java.io.File;
    import java.io.IOException;
    import java.io.UnsupportedEncodingException;
    
    import javax.servlet.http.HttpServletRequest;
    
    import org.apache.commons.io.FileUtils;
    import org.springframework.http.HttpHeaders;
    import org.springframework.http.HttpStatus;
    import org.springframework.http.MediaType;
    import org.springframework.http.ResponseEntity;
    import org.springframework.stereotype.Controller;
    import org.springframework.web.bind.annotation.RequestMapping;
    
    @Controller
    public class Download { 
        @RequestMapping("/todownload")
        public String todownload() {
            return "download";
        }
    
        @RequestMapping("/download")
        public ResponseEntity<byte[]> fileDownload(String filename, HttpServletRequest request) {
            String path = "D:/程序测试/要给客户下载的文件/";
            String filename2 = null;
            try {
                //解决找到文件问题:
                // URLEonder把中文用UTF-8编码,然而,tomcat用iso-8859-1解码
                //,我们需要用iso-8859-1编码,再重新用utf-8解码才能匹配到硬盘文件的名字
                filename2 = new String(filename.getBytes("ISO-8859-1"), "UTF-8");
            } catch (UnsupportedEncodingException e1) {
                e1.printStackTrace();
            }
            File file = new File(path + filename2);
            HttpHeaders headers = new HttpHeaders();
    
    
            String filename3 = null;
            try {
                //解决提示下载框的中文问题:
                // 所有浏览器都会使用本地编码，即中文操作系统使用GBK
                // 浏览器收到这个文件名后，会使用iso-8859-1来解码
                //编码流程:把中文用GBK编码为字节数组,再用ISO-8859-1编码,浏览器先用ISO-8859-1解码为字节数组,在用GBK解码为中文
                filename3 = new String(filename2.getBytes("GBK"), "ISO-8859-1");
            } catch (UnsupportedEncodingException e1) {
                e1.printStackTrace();
            }
    
            headers.setContentDispositionFormData("attachment", filename3);
            headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);
            try {
                return new ResponseEntity<byte[]>(FileUtils.readFileToByteArray(file), headers, HttpStatus.OK);
            } catch (IOException e) {
                e.printStackTrace();
            }
            return null;
        }
    }