009 spring boot中文件的上传与下载

一：任务

1.任务

　　文件的上传

　　文件的下载

二：文件的上传

1.新建一个对象

　　FileInfo.java

 package com.cao.dto;

 public class FileInfo {
     private String path;
     public FileInfo(String path) {
         this.path=path;
     }
     public String getPath() {
         return path;
     }
     public void setPath(String path) {
         this.path = path;
     }

 }

2.新建控制器

 package com.cao.web.controller;

 import java.io.File;
 import java.io.IOException;
 import java.util.Date;

 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;

 import com.cao.dto.FileInfo;

 @RestController
 @RequestMapping("/file")
 public class FileController {
     @PostMapping
     public FileInfo uploadFile(MultipartFile fileKey) throws Exception {
         System.out.println("fileName: "+fileKey.getName());
         System.out.println("OriginalFilename: "+fileKey.getOriginalFilename());
         System.out.println("size: "+fileKey.getSize());
         //将要存储在controller的目录下
         String folder="E:\\workspace-sts-3.9.5.RELEASE\\it-security-demo\\src\\main\\java\\com\\cao\\web\\controller";
         File localFile=new File(folder,new Date().getTime()+".txt");
         fileKey.transferTo(localFile);
         //写入流中，这个主要用于写入其他的地方，例如服务器等，这里不写了
         //fileKey.getInputStream()
         return new FileInfo(localFile.getAbsolutePath());
     }
 }

3.测试类

 /**
      * 测试文件的上传
      * @throws Exception
      */
     @Test
     public void whenUploadSuccess() throws Exception {
         String result=mockMvc.perform(MockMvcRequestBuilders.fileUpload("/file")
                 .file(new MockMultipartFile("fileKey","test.txt","multipart/form-data","hello".getBytes("UTF-8"))))
                 .andExpect(MockMvcResultMatchers.status().isOk())
                 .andReturn().getResponse().getContentAsString();
         System.out.println("result="+result);
     }

4.控制台

　　

　　存储到的现象

　　

三：文件的下载

1.添加io操作的包

           <dependency>
             <groupId>commons-io</groupId>
             <artifactId>commons-io</artifactId>
           </dependency>

2.文件下载的程序

 package com.cao.web.controller;

 import java.io.File;
 import java.io.FileInputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
 import java.util.Date;

 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;

 import org.apache.commons.io.IOUtils;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.multipart.MultipartFile;

 import com.cao.dto.FileInfo;

 @RestController
 @RequestMapping("/file")
 public class FileController {

     String folder="E:\\workspace-sts-3.9.5.RELEASE\\it-security-demo\\src\\main\\java\\com\\cao\\web\\controller";

     /**
      * 文件的上传控制器
      * @param fileKey
      * @return
      * @throws Exception
      */
     @PostMapping
     public FileInfo uploadFile(MultipartFile fileKey) throws Exception {
         System.out.println("fileName: "+fileKey.getName());
         System.out.println("OriginalFilename: "+fileKey.getOriginalFilename());
         System.out.println("size: "+fileKey.getSize());
         //将要存储在controller的目录下
         File localFile=new File(folder,new Date().getTime()+".txt");
         fileKey.transferTo(localFile);
         //写入流中，这个主要用于写入其他的地方，例如服务器等，这里不写了
         //fileKey.getInputStream()
         return new FileInfo(localFile.getAbsolutePath());
     }

     /**
      * 文件的下载
      */
     @GetMapping("/{id}")
     public void downFile(@PathVariable String id, HttpServletRequest request,HttpServletResponse response) {
         try(
             InputStream inputStream=new FileInputStream(new File(folder,id+".txt"));
             OutputStream outputStream=response.getOutputStream();
             )
         {
             response.setContentType("application/x-download");
             response.addHeader("Content-Disposition", "attachment;filename=test.txt");
             IOUtils.copy(inputStream, outputStream);
             outputStream.flush();
         } catch (Exception e) {
             // TODO: handle exception
         }
     }

 }

3.在浏览器*问