如何在spring batch中使用sftp上传多个文件

@Configuration
@EnableBatchProcessing
public class BatchConfiguration {

    @Autowired
    private JobBuilderFactory jobBuilderFactory;

    @Autowired
    private StepBuilderFactory stepBuilderFactory;

    @Autowired
    private SftpSessionFactory sftpSessionFactory;

    @Bean
    public ItemWriter<File> sftpFileWriter() {
        SftpResourceSuffixCreator suffixCreator = new SftpResourceSuffixCreator();
        suffixCreator.setSuffix(".txt"); // 设置上传文件的后缀名

        SftpResourceSuffixCreator suffixCreator = new SftpResourceSuffixCreator();
        suffixCreator.setSuffix(".txt"); // 设置上传文件的后缀名

        SftpFileWriter writer = new SftpFileWriter(sftpSessionFactory);
        writer.setResourceSuffixCreator(suffixCreator);

        return writer;
    }

    @Bean
    public Step sftpUploadStep(ItemWriter<File> sftpFileWriter) {
        return stepBuilderFactory.get("sftpUploadStep")
                .<File, File>chunk(10)
                .reader(sftpFileReader())
                .writer(sftpFileWriter)
                .build();
    }

    @Bean
    public Job sftpUploadJob(Step sftpUploadStep) {
        return jobBuilderFactory.get("sftpUploadJob")
                .start(sftpUploadStep)
                .build();
    }

    public static void main(String[] args) {
        SpringApplication.run(BatchConfiguration.class, args);
    }
}