如何在Spring Boot中读取Blob

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
</dependency>

@Entity
@Table(name = "your_table_name")
public class YourEntity {
    // other fields
    
    @Lob
    @Column(name = "blob_data")
    private byte[] blobData;
    
    // getters and setters
}

public interface YourRepository extends JpaRepository<YourEntity, Long> {
    // other methods
    
    YourEntity findById(long id);
}

@RestController
@RequestMapping("/your-endpoint")
public class YourController {
    private YourRepository yourRepository;
    
    @Autowired
    public YourController(YourRepository yourRepository) {
        this.yourRepository = yourRepository;
    }
    
    @GetMapping("/{id}")
    public ResponseEntity<byte[]> getBlobData(@PathVariable long id) {
        YourEntity entity = yourRepository.findById(id);
        if (entity != null && entity.getBlobData() != null) {
            HttpHeaders headers = new HttpHeaders();
            headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);
            headers.setContentLength(entity.getBlobData().length);
            return new ResponseEntity<>(entity.getBlobData(), headers, HttpStatus.OK);
        } else {
            return new ResponseEntity<>(HttpStatus.NOT_FOUND);
        }
    }
}