Spring Boot 图片上传功能代码示例

以下是一个使用 Spring Boot 实现图片上传的示例代码：

创建一个上传图片的控制器类

import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.util.StringUtils;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;
import javax.servlet.http.HttpServletRequest;
import java.io.File;
import java.io.IOException;

@RestController
@RequestMapping('/api')
public class FileUploadController {

    private static final String UPLOAD_DIR = 'uploads';

    @PostMapping('/upload')
    public ResponseEntity<String> uploadFile(@RequestParam('file') MultipartFile file, HttpServletRequest request) {
        String fileName = StringUtils.cleanPath(file.getOriginalFilename());
        String uploadDir = request.getServletContext().getRealPath('') + UPLOAD_DIR;
        try {
            FileUploadUtil.saveFile(uploadDir, fileName, file);
        } catch (IOException e) {
            return new ResponseEntity<'Could not upload the file: ' + fileName, HttpStatus.BAD_REQUEST);
        }
        return new ResponseEntity<'File uploaded successfully: ' + fileName, HttpStatus.OK);
    }
}

创建一个文件上传工具类

import org.springframework.web.multipart.MultipartFile;
import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;

public class FileUploadUtil {

    public static void saveFile(String uploadDir, String fileName, MultipartFile multipartFile) throws IOException {
        Path uploadPath = Paths.get(uploadDir);
        if (!Files.exists(uploadPath)) {
            Files.createDirectories(uploadPath);
        }
        try {
            multipartFile.transferTo(new File(uploadDir + '/' + fileName));
        } catch (IOException e) {
            throw new IOException('Could not save file: ' + fileName, e);
        }
    }
}

在 application.properties 文件中配置文件上传的最大大小

spring.servlet.multipart.max-file-size=10MB

这样，你就可以在 Spring Boot 应用程序中使用 Java 编写图片上传功能了。