我是 Spring Boot 新手,在编写文件上传 API 时出现以下错误:
Error:Description:
Field fileStorageService in com.primesolutions.fileupload.controller.FileController required a bean of type 'com.primesolutions.fileupload.service.FileStorageService' that could not be found.
The injection point has the following annotations:
- @org.springframework.beans.factory.annotation.Autowired(required=true)
Action:
Consider defining a bean of type 'com.primesolutions.fileupload.service.FileStorageService' in your configuration.*
Controller 类:
public class FileController
{
private static final Logger logger = LoggerFactory.getLogger(FileController.class);
@Autowired
private FileStorageService fileStorageService;
@PostMapping("/uploadFile")
public UploadFileResponse uploadFile(@RequestParam("file") MultipartFile file) {
String fileName = fileStorageService.storeFile(file);
String fileDownloadUri = ServletUriComponentsBuilder.fromCurrentContextPath()
.path("/downloadFile/")
.path(fileName)
.toUriString();
return new UploadFileResponse(fileName, fileDownloadUri,
file.getContentType(), file.getSize());
}
@PostMapping("/uploadMultipleFiles")
public List<UploadFileResponse> uploadMultipleFiles(@RequestParam("files") MultipartFile[] files) {
return Arrays.asList(files)
.stream()
.map(file -> uploadFile(file))
.collect(Collectors.toList());
}
}
服务等级:
private final Path fileStorageLocation;
@Autowired
public FileStorageService(FileStorageProperties fileStorageProperties) {
this.fileStorageLocation = Paths.get(fileStorageProperties.getUploadDir())
.toAbsolutePath().normalize();
try {
Files.createDirectories(this.fileStorageLocation);
} catch (Exception ex) {
throw new FileStorageException("Could not create the directory where the uploaded files will be stored.", ex);
}
}
public String storeFile(MultipartFile file) {
// Normalize file name
String fileName = StringUtils.cleanPath(file.getOriginalFilename());
try {
// Check if the file's name contains invalid characters
if(fileName.contains("..")) {
throw new FileStorageException("Sorry! Filename contains invalid path sequence " + fileName);
}
// Copy file to the target location (Replacing existing file with the same name)
Path targetLocation = this.fileStorageLocation.resolve(fileName);
Files.copy(file.getInputStream(), targetLocation, StandardCopyOption.REPLACE_EXISTING);
return fileName;
} catch (IOException ex) {
throw new FileStorageException("Could not store file " + fileName + ". Please try again!", ex);
}
}
配置类:
@ConfigurationProperties(prefix = "file")
public class FileStorageProperties {
private String uploadDir;
public String getUploadDir()
{
return uploadDir;
}
public void setUploadDir(String uploadDir) {
this.uploadDir = uploadDir;
}
}
主要的:
@SpringBootApplication
@EnableConfigurationProperties({
FileStorageProperties.class
})
public class FileApplication {
public static void main(String[] args) {
SpringApplication.run(FileApplication.class, args);
}
}
属性文件
## MULTIPART (MultipartProperties)
# Enable multipart uploads
spring.servlet.multipart.enabled=true
# Threshold after which files are written to disk.
spring.servlet.multipart.file-size-threshold=2KB
# Max file size.
spring.servlet.multipart.max-file-size=200MB
# Max Request Size
spring.servlet.multipart.max-request-size=215MB
## File Storage Properties
# All files uploaded through the REST API will be stored in this directory
file.upload-dir=C:/Projects/SpringBootProject/Primesolutions/PrimeSolutions/FileUpload
我正在尝试读取文件上传属性并将其传递给 Controller 类。
最佳答案
该错误似乎表明 Spring 不知道任何类型的 bean com.primesolutions.fileupload.service.FileStorageService
.
正如评论中所说,确保你上课 FileStorageService
由 @Service
注释或 @Component
:
@Service
public class FileStorageService {
...
}
还要确保这个类位于你的类的子包中
FileApplication
.例如,如果您的 FileApplication
类位于包中com.my.package
,请确保您的 FileStorageService
位于 com.my.package.** 包中(相同的包或任何子包)。顺便提一下改进代码的几点注意事项:
@Autowired
在构造函数上是可选的。 @PostConstruct
注解。
@Service
public class FileStorageService {
private FileStorageProperties props;
// @Autowired is optional in this case
public FileStorageService (FileStorageProperties fileStorageProperties) {
this.props = fileStorageProperties;
this.fileStorageLocation = Paths.get(fileStorageProperties.getUploadDir())
.toAbsolutePath().normalize();
}
@PostConstruct
public void init() {
try {
Files.createDirectories(this.fileStorageLocation);
} catch (Exception ex) {
throw new FileStorageException("Could not create the directory where the uploaded files will be stored.", ex);
}
}
}
@Autowired
在一个领域。请改用构造函数。它更适合您的测试,并且更易于维护:public class FileController {
private FileStorageService service;
public FileController(FileStorageService service) {
this.service = service;
}
}
关于java - 注入(inject)点有如下注解 : - @org. springframework.beans.factory.annotation.Autowired(required=true),我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/59993124/