一、pom文件依赖的添加
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency> <dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency> <dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
</dependencies>
二、controller层
@Controller
public class FileUploadController {
private final StorageService storageService; @Autowired
public FileUploadController(StorageService storageService) {
this.storageService = storageService;
} //展示上传过的文件
@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";
} //下载选定的上传的文件
@GetMapping("/files/{filename:.+}")
@ResponseBody
public ResponseEntity<Resource> serveFile(@PathVariable String filename) { Resource file = storageService.loadAsResource(filename);
return ResponseEntity
.ok()
.header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\""+file.getFilename()+"\"")
.body(file);
} //上传文件
@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();
}
}
三、实现的service层
@Service
public class FileSystemStorageService implements StorageService { private final Path rootLocation; @Autowired
public FileSystemStorageService(StorageProperties properties) {
this.rootLocation = Paths.get(properties.getLocation());
} @Override
public void store(MultipartFile file) {
try {
if (file.isEmpty()) {
throw new StorageException("Failed to store empty file " + file.getOriginalFilename());
}
Files.copy(file.getInputStream(), this.rootLocation.resolve(file.getOriginalFilename()));
} catch (IOException e) {
throw new StorageException("Failed to store file " + file.getOriginalFilename(), e);
}
} @Override
public Stream<Path> loadAll() {
try {
return Files.walk(this.rootLocation, )
.filter(path -> !path.equals(this.rootLocation))
.map(path -> this.rootLocation.relativize(path));
} 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.createDirectory(rootLocation);
} catch (IOException e) {
throw new StorageException("Could not initialize storage", e);
}
}
}
四、在application.properties文件上配置上传的属性
spring.http.multipart.max-file-size=128KB
spring.http.multipart.max-request-size=128KB
五、服务启动时的处理
六、测试成功的结果