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环境与配置

添加 maven 依赖

   			
    
     org.springframework.boot
    			
    
     spring-boot-starter-thymeleaf
    		
   		
   			
    
     org.springframework.boot
    			
    
     spring-boot-starter-web
    		
   		
   		
   			
    
     org.springframework.boot
    			
    
     spring-boot-devtools
    			
    
     true
    		
   

application.yml 配置文件

spring:  servlet:    multipart:      max-file-size: 1024KB # 单个文件大小      max-request-size: 1024KB # 一次请求文件大小

代码

文件上传服务接口 ，实现初始化，存储，查询等方法。

public interface StorageService {    void init();    void store(MultipartFile file);    Stream
   
     loadAll();    Path load(String filename);    Resource loadAsResource(String filename);    void deleteAll();}
   

StorageService 接口实现类

@Servicepublic class FileSystemStorageService implements StorageService {    private final Path rootLocation;    @Autowired    public FileSystemStorageService(StorageProperties properties) {        //获取文件存储路径        this.rootLocation = Paths.get(properties.getLocation());    }    //上传文件    @Override    public void store(MultipartFile file) {        String filename = StringUtils.cleanPath(file.getOriginalFilename());        try {            if (file.isEmpty()) {                throw new StorageException("Failed to store empty file " + filename);            }            if (filename.contains("..")) {                // This is a security check                throw new StorageException(                        "Cannot store file with relative path outside current directory "                                + filename);            }            try (InputStream inputStream = file.getInputStream()) {                Files.copy(inputStream, this.rootLocation.resolve(filename),                        StandardCopyOption.REPLACE_EXISTING);            }        }        catch (IOException e) {            throw new StorageException("Failed to store file " + filename, e);        }    }        @Override    public Stream
   
     loadAll() {        try {            return Files.walk(this.rootLocation, 1)                    .filter(path -> !path.equals(this.rootLocation))                    .map(this.rootLocation::relativize);        }        catch (IOException e) {            throw new StorageException("Failed to read stored files", e);        }    }    @Override    public Path load(String filename) {        return rootLocation.resolve(filename);    }    @Override    public Resource loadAsResource(String filename) {        try {            Path file = load(filename);            Resource resource = new UrlResource(file.toUri());            if (resource.exists() || resource.isReadable()) {                return resource;            }            else {                throw new StorageFileNotFoundException(                        "Could not read file: " + filename);            }        }        catch (MalformedURLException e) {            throw new StorageFileNotFoundException("Could not read file: " + filename, e);        }    }    @Override    public void deleteAll() {        FileSystemUtils.deleteRecursively(rootLocation.toFile());    }    @Override    public void init() {        try {            Files.createDirectories(rootLocation);        }        catch (IOException e) {            throw new StorageException("Could not initialize storage", e);        }    }}
   

文件存储的目录配置，运行项目是会在项目根目录创建 upload-dir 文件夹。

@ConfigurationProperties("storage")public class StorageProperties {    /**     * Folder location for storing files     */    private String location = "upload-dir";    public String getLocation() {        return location;    }    public void setLocation(String location) {        this.location = location;    }}

异常处理

public class StorageException extends RuntimeException {    public StorageException(String message) {        super(message);    }    public StorageException(String message, Throwable cause) {        super(message, cause);    }}

public class StorageFileNotFoundException extends StorageException {    public StorageFileNotFoundException(String message) {        super(message);    }    public StorageFileNotFoundException(String message, Throwable cause) {        super(message, cause);    }}

控制层

@Controllerpublic class FileUploadController {    private final StorageService storageService;    @Autowired    public FileUploadController(StorageService storageService) {        this.storageService = storageService;    }    @GetMapping("/")    public String listUploadedFiles(Model model) throws IOException {        model.addAttribute("files", storageService.loadAll().map(                path -> MvcUriComponentsBuilder.fromMethodName(FileUploadController.class,                        "serveFile", path.getFileName().toString()).build().toString())                .collect(Collectors.toList()));        return "uploadForm";    }    @GetMapping("/files/{filename:.+}")    @ResponseBody    public ResponseEntity
   
     serveFile(@PathVariable String filename) {        Resource file = storageService.loadAsResource(filename);        return ResponseEntity.ok().header(HttpHeaders.CONTENT_DISPOSITION,                "attachment; filename=\"" + file.getFilename() + "\"").body(file);    }    @PostMapping("/")    public String handleFileUpload(@RequestParam("file") MultipartFile file,                                   RedirectAttributes redirectAttributes) {        storageService.store(file);        redirectAttributes.addFlashAttribute("message",                "You successfully uploaded " + file.getOriginalFilename() + "!");        return "redirect:/";    }    @ExceptionHandler(StorageFileNotFoundException.class)    public ResponseEntity
     handleStorageFileNotFound(StorageFileNotFoundException exc) {        return ResponseEntity.notFound().build();    }}
   

启动类

//参考 ： https://spring.io/guides/gs/uploading-files/@SpringBootApplication@EnableConfigurationProperties(StorageProperties.class)public class SpringBootFileUploadApplication {	public static void main(String[] args) {		SpringApplication.run(SpringBootFileUploadApplication.class, args);	}	//初始化，创建文件夹	@Bean	CommandLineRunner init(StorageService storageService) {		return (args) -> {			storageService.deleteAll();			storageService.init();		};	}}

前端代码 uploadForm.html

   
    
    
   
   
    
    
        
     
                  
       
        
File to upload:
        
       
                   
        
        
       
              
     
    
    
   
   
    
    
        
     
                    
    
    
   

项目结构

运行结果

公众号：【星尘Pro】

github：

推荐阅读

源码下载：https://github.com/huangliangyun/Spring-Boot-2.X

参考：https://spring.io/guides/gs/uploading-files/

https://github.com/spring-guides/gs-uploading-files

转载地址：http://udfsi.baihongyu.com/