springboot成神之——spring文件下载功能

• 本文介绍spring文件下载功能
  • 目录结构
  • DemoApplication
  • WebConfig
  • TestController
  • MediaTypeUtils
  • 前端测试

本文介绍spring文件下载功能

目录结构

DemoApplication

package com.springlearn.learn;

import org.springframework.boot.SpringApplication;

import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication

public class DemoApplication {

	public static void main(String[] args) {

		SpringApplication.run(DemoApplication.class, args);

	}

}

WebConfig

package com.springlearn.learn.config;

import org.springframework.context.annotation.Configuration;

import org.springframework.web.servlet.config.annotation.CorsRegistry;

import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

@Configuration

public class WebConfig implements WebMvcConfigurer {

    @Override

    public void addCorsMappings(CorsRegistry registry) {

        registry.addMapping("/**").allowedOrigins("*").allowedMethods("GET", "POST", "PUT", "DELETE").allowedOrigins("*")

        .allowedHeaders("*");

    }

}

TestController

package com.springlearn.learn.controller;

import java.io.BufferedInputStream;

import java.io.BufferedOutputStream;

import java.io.File;

import java.io.FileInputStream;

import java.io.IOException;

import javax.servlet.ServletContext;

import javax.servlet.http.HttpServletResponse;

import com.springlearn.learn.utils.MediaTypeUtils;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.http.HttpHeaders;

import org.springframework.http.MediaType;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RequestMethod;

import org.springframework.web.bind.annotation.RequestParam;

import org.springframework.web.bind.annotation.ResponseBody;

import org.springframework.web.bind.annotation.RestController;

@RestController

public class TestController {

    @Autowired

    private ServletContext servletContext;

    @ResponseBody

    @RequestMapping(value = "/DownLoadTest", method = RequestMethod.GET)

    public void Test(@RequestParam(defaultValue = "spring-boot-reference.pdf") String fileName, HttpServletResponse response) throws IOException {

        MediaType mediaType = MediaTypeUtils.getMediaTypeForFileName(this.servletContext, fileName);

        System.out.println("fileName: " + fileName);

        System.out.println("mediaType: " + mediaType);

        String filepath = "C:\\Users\\26401\\Desktop\\learn";

        File file = new File(filepath + File.separator + fileName);

        response.setContentType(mediaType.getType());

        response.setHeader(HttpHeaders.CONTENT_DISPOSITION, "attachment;filename=" + file.getName());

        response.setContentLength((int) file.length());

        BufferedInputStream inStream = new BufferedInputStream(new FileInputStream(file));

        BufferedOutputStream outStream = new BufferedOutputStream(response.getOutputStream());

        byte[] buffer = new byte[1024];

        int bytesRead = 0;

        while ((bytesRead = inStream.read(buffer)) != -1) {

            outStream.write(buffer, 0, bytesRead);

        }

        outStream.flush();

        inStream.close();

    }

}

MediaTypeUtils

package com.springlearn.learn.utils;

import javax.servlet.ServletContext;

import org.springframework.http.MediaType;

public class MediaTypeUtils {

    public static MediaType getMediaTypeForFileName(ServletContext servletContext, String fileName) {

        String mineType = servletContext.getMimeType(fileName);

        try {

            MediaType mediaType = MediaType.parseMediaType(mineType);

            return mediaType;

        } catch (Exception e) {

            return MediaType.APPLICATION_OCTET_STREAM;

        }

    }

}

前端测试

直接访问 http://localhost:9001/DownLoadTest 即可