how to store and retrieve image files from database using springboot - database

Question

I'm building an angular springboot application but I find so many approaches to do this some of which I honestly do not understand.
how can I store 1 or more images at a time and retrieve them.

Answer 1

You can use #Lob to store Images or Any Files in the Database. The following example shows a simple implementation of this approach
#Entity
#Table(name = "file")
public class File {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#Column(name = "uuid")
private String uuid;
#Column(name = "content_type")
private String contentType;
#Column(name = "extension")
private String extension;
#Lob
#Column(name = "content", columnDefinition = "LONGBLOB")
private byte[] content;
}
#Service
public class FileService {
private final FileRepository repository;
#Autowired
public FileService(FileRepository repository) {
this.repository = repository;
}
#Transactional
public StreamingResponseBody download(Long id, HttpServletResponse response) {
final File file = repository.findById(id).orElseThrow(NotFoundException::new);
return outputStream -> {
String fileName = (file.getUuid() + file.getExtension()).trim();
response.setContentType(file.getContentType());
response.setHeader("Content-Disposition", "attachment; filename=" + fileName);
outputStream.write(file.getContent());
outputStream.flush();
};
}
public FileDto create(MultipartFile multipartFile, boolean general) {
String fileName = multipartFile.getOriginalFilename();
String fileExtension = Objects.requireNonNull(fileName).substring(fileName.lastIndexOf('.'));
String uuid = UUID.randomUUID().toString();
UserDto user = contextUtils.getPrincipal();
File file = new File();
file.setUuid(uuid);
file.setContentType(multipartFile.getContentType());
file.setExtension(fileExtension);
file.setGeneral(general);
file.setContent(multipartFile.getBytes());
file.setId(repository.save(file).getId());
return file;
}
}