Apache Mina Ftplet - onUploadStart没有保存文件

import org.apache.ftpserver.ftplet.FtpException;
import org.apache.ftpserver.ftplet.FtpFile;
import org.apache.ftpserver.ftplet.FtpletResult;
import org.apache.ftpserver.ftplet.UploadRequest;
import org.apache.ftpserver.ftplet.UploadStatistics;
import org.apache.ftpserver.ftplet.User;
import org.apache.ftpserver.ftplet.FileSystemView;
import org.apache.ftpserver.ftplet.FtpSession;
import org.apache.ftpserver.ftplet.DefaultFtpFile;

public class CustomFtplet extends DefaultFtplet {
    
    @Override
    public FtpletResult onUploadStart(FtpSession session, FtpRequest request) throws FtpException, IOException {
        // 获取上传文件的信息
        String fileName = request.getArgument();
        long fileSize = request.getContentLength();
        
        // 获取用户信息
        User user = session.getUser();
        String username = user.getName();
        
        // 获取文件保存路径
        FileSystemView fsView = session.getFileSystemView();
        FtpFile homeDir = fsView.getHomeDirectory();
        String savePath = homeDir.getAbsolutePath() + "/" + fileName;
        
        // 保存文件到指定路径
        File uploadedFile = new File(savePath);
        // 进行文件保存操作，这里只是示例，具体实现根据需求自行编写
        
        // 返回继续上传
        return FtpletResult.DEFAULT;
    }
}