问题
I followed tutorial for uploading files but I end up with the following error:
Parameter 0 of constructor in nu.pk.cv.storage.FileSystemStorageService required a bean of type 'nu.pk.cv.storage.StorageProperties' that could not be found.
Action:
Consider defining a bean of type 'nu.pk.cv.storage.StorageProperties' in your configuration
The only difference that I know that I have done is that I use @RestController instead of only @Controller And that I have my controller in another subpackage and not in the parent package. My storage classes are in nu.pk.cv.storage while my controller is in nu.pk.cv.cv.
StorageProperties
package nu.pk.cv.storage;
@ConfigurationProperties("storage")
public class StorageProperties {
private String location = "/tmp/cv-gen";
public String getLocation() {
return location;
}
public void setLocation(String location) {
this.location = location;
}
}
FileSystemStorageService
package nu.pk.cv.storage;
@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) {
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 the file with relative path outside the 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<Path> 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);
}
}
}
My controller
package nu.pk.cv.cv;
@RestController
public class CV {
@Autowired
private StorageService storageService;
@PostMapping("/api/cv/generate")
public String generate(@RequestParam("files") MultipartFile file) {
storageService.store(file);
return "Mjau";
}
}
回答1:
According to Baeldung article you need to add also @Configuration to your class:
@Configuration
@ConfigurationProperties("storage")
public class StorageProperties
回答2:
add annotation @Configuration or @Component at StorageProperties class.
@Configuration
@ConfigurationProperties("storage")
public class StorageProperties {
or
@Component
@ConfigurationProperties("storage")
public class StorageProperties {
if you receive an Error like "a bean not found or a bean of type configuration", then you have to check your @Component, @Service or @Repository annotations in the related classes.
ref: Spring blog
来源：https://stackoverflow.com/questions/52180328/spring-error-parameter-0-of-constructor-in-service-required-a-bean-of-type-con