springboot 实现文件的上传和下载

关键的controller

package com.yuanshijia.securitydemo.controller;

import com.yuanshijia.securitydemo.domain.FileInfo;
import org.apache.tomcat.util.http.fileupload.IOUtils;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.util.Date;

/**
 * 文件controller
 */
@RestController
@RequestMapping("/file")
public class FileController {
    //存放文件的路径 ，这里直接放到controller文件夹下

    private static final String folder = "/Users/yuan/Documents/java/springboot/imooc_security/security-demo/src/main/java/com/yuanshijia/securitydemo/controller";

    /**
     * 文件上传
     * @param file
     * @return
     * @throws IOException
     */
    @PostMapping
    public FileInfo update(MultipartFile file) throws IOException {
        /**
         * 注意：file名字要和参入的name一致
         */

        System.out.println("file name=" + file.getName());
        System.out.println("origin file name=" + file.getOriginalFilename());
        System.out.println("file size=" + file.getSize());



        /**
         * 这里是写到本地
     * 还可以用file.getInputStrem()
         * 获取输入流，然后存到阿里oss。。或七牛。。
         */
        File localFile = new File(folder, new Date().getTime() + ".txt");

        //把传入的文件写到本地文件
        file.transferTo(localFile);

        return new FileInfo(localFile.getAbsolutePath()); //getAbsolutePath为绝对路径

    }

    /**
     * 文件的下载
   */
    @GetMapping("/{id}") //id为时间戳
    public void download(@PathVariable("id") String id, HttpServletRequest request, HttpServletResponse response) {

        try (
                //jdk7新特性，可以直接写到try()括号里面，java会自动关闭
         InputStream inputStream = new FileInputStream(new File(folder, id + ".txt"));
                OutputStream outputStream = response.getOutputStream()
        ) {
            //指明为下载
            response.setContentType("application/x-download");
            String fileName = "test.txt";
            response.addHeader("Content-Disposition", "attachment;fileName=" + fileName);   // 设置文件名


            //把输入流copy到输出流
       IOUtils.copy(inputStream, outputStream);

            outputStream.flush();
            
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }
    


    
}

文件信息类

FileInfo

/**
 * 文件信息
 */
public class FileInfo {

    private String path;

    public FileInfo(String path) {
        this.path = path;
    }


    public FileInfo() {
    }

    public String getPath() {
        return path;
    }

    public void setPath(String path) {
        this.path = path;
    }
}

测试类

import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.http.MediaType;
import org.springframework.mock.web.MockMultipartFile;
import org.springframework.test.context.junit4.SpringRunner;
import org.springframework.test.web.servlet.MockMvc;
import org.springframework.test.web.servlet.request.MockMvcRequestBuilders;
import org.springframework.test.web.servlet.result.MockMvcResultMatchers;
import org.springframework.test.web.servlet.setup.MockMvcBuilders;
import org.springframework.web.context.WebApplicationContext;

import java.util.Date;

@RunWith(SpringRunner.class)
@SpringBootTest
public class UserControllerTest {

    @Autowired
    private WebApplicationContext webApplicationContext;

    private MockMvc mockMvc;

    @Before
    public void init(){
        mockMvc = MockMvcBuilders.webAppContextSetup(webApplicationContext).build();
    }

  

    /**
     * 文件上传
     */
    @Test                                                    
    public void whenUploadSuccess() throws Exception {
        String result = mockMvc.perform(MockMvcRequestBuilders.fileUpload("/file")  //就是post
                .file(new MockMultipartFile("file", "text.txt", "multipart/form-data", "hello upload".getBytes("UTF-8"))))   //模拟文件上传
                .andExpect(MockMvcResultMatchers.status().isOk())
                .andReturn().getResponse().getContentAsString()
                ;
        System.out.println("result=" + result);
        

    }

}

上传的结果：

下载结果：

在浏览器输入：http://localhost:8080/file/1525500214929 

test就是设置的文件名了，查看内容：