spring boot 解决生产环境下多线程调用FTP流被关闭问题

public class FtpUtil {
}

@Configuration
public class FtpUtilConfig {

    @Autowired
    private FtpProperties ftpProperties;
    @Bean
    @Scope("prototype")
    public FtpUtil ftpUtil () {
        FtpUtil ftpUtil = new FtpUtil();
        return ftpUtil;
    }

}

@Configuration
@ComponentScan("com.fund.common")
public class FtpScope{
    public static void main(String[] args) {
        AnnotationConfigApplicationContext context =
                new AnnotationConfigApplicationContext(FtpScope.class);
        FtpUtil f1 = context.getBean(FtpUtil.class);
        FtpUtil f2 = context.getBean(FtpUtil.class);

        System.out.println(p1);
        System.out.println(p2);
    }
}

com.fund.common.util.FtpUtil@7dac3fd8
com.fund.common.util.FtpUtil@425357dd