使用Java读取本地文件并转换为MultipartFile对象的方法

import java.io.FileInputStream;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import org.springframework.web.multipart.MultipartFile;
 
/**
 * 读取本地文件
 * @param name 文件名
 * @return MultipartFile
 */
public MultipartFile getFile(String name) {
    // 构建文件的完整路径
    String filePath = String.format("D:\\Users\\Administrator\\Desktop\\Doc\\%s", name);
 
    // 获取路径对象
    Path path = Paths.get(filePath);
    // 获取文件名
    String fileName = path.getFileName().toString();
    String contentType;
    byte[] content;
 
    try (FileInputStream fis = new FileInputStream(filePath)) {
        // 获取文件的内容类型
        contentType = Files.probeContentType(path);
        // 读取文件内容到字节数组
        content = fis.readAllBytes();
        // 创建并返回一个 CustomMultipartFile 对象
        return new CustomMultipartFile(fileName, fileName, contentType, content);
    } catch (IOException e) {
        // 打印错误信息，便于调试
        e.printStackTrace();
        // 返回 null 表示读取文件失败
        return null;
    }
}

import org.springframework.web.multipart.MultipartFile;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
 
public class CustomMultipartFile implements MultipartFile {
    private final String name;
    private final String originalFilename;
    private final String contentType;
    private final byte[] content;
 
    public CustomMultipartFile(String name, String originalFilename, String contentType, byte[] content) {
        this.name = name;
        this.originalFilename = originalFilename;
        this.contentType = contentType;
        this.content = content;
    }
 
    @Override
    public String getName() {
        return this.name;
    }
 
    @Override
    public String getOriginalFilename() {
        return this.originalFilename;
    }
 
    @Override
    public String getContentType() {
        return this.contentType;
    }
 
    @Override
    public boolean isEmpty() {
        return this.content.length == 0;
    }
 
    @Override
    public long getSize() {
        return this.content.length;
    }
 
    @Override
    public byte[] getBytes() throws IOException {
        return this.content;
    }
 
    @Override
    public InputStream getInputStream() throws IOException {
        return new ByteArrayInputStream(this.content);
    }
 
    @Override
    public void transferTo(java.io.File dest) throws IOException, IllegalStateException {
        throw new UnsupportedOperationException("Not implemented");
    }
}