在Spring Boot中使用PostgreSQL存储图片时，你可以将图片转换为字节流（byte array）并存储到Blob字段中。以下是一个简化的例子：
- 实体类（ImageEntity.java）:
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Lob;
@Entity
public class ImageEntity {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
@Lob
private byte[] imageData;
// 标准的getter和setter
// ...
}- Repository接口（ImageRepository.java）:
import org.springframework.data.jpa.repository.JpaRepository;
public interface ImageRepository extends JpaRepository<ImageEntity, Long> {
}- 服务类（ImageService.java）:
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.web.multipart.MultipartFile;
import java.io.IOException;
@Service
public class ImageService {
@Autowired
private ImageRepository imageRepository;
public ImageEntity saveImage(MultipartFile file) throws IOException {
ImageEntity imageEntity = new ImageEntity();
imageEntity.setImageData(file.getBytes());
return imageRepository.save(imageEntity);
}
public byte[] getImage(Long id) {
ImageEntity imageEntity = imageRepository.findById(id).orElse(null);
return imageEntity == null ? null : imageEntity.getImageData();
}
}- 控制器类（ImageController.java）:
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.MediaType;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;
@RestController
@RequestMapping("/images")
public class ImageController {
@Autowired
private ImageService imageService;
@PostMapping
public ImageEntity saveImage(@RequestParam("file") MultipartFile file) throws IOException {
return imageService.saveImage(file);
}
@GetMapping("/{id}")
@ResponseBody
public byte[] getImage(@PathVariable Long id) {
return imageService.getImage(id);
}
}在这个例子中，我们使用了Spring Data JPA来简化数据访问层的代码。saveImage方法将MultipartFile转换为字节流并保存到数据库中，而getImage方法则从数据库中检索图片数据并以字节流的形式返