Spring Integration FTP：下载完成后移动远程文件至远程归档目录

远程FTP服务器目录结构如下：

• test/
  • abc.txt
  • xyz.txt
  • archive/

我们已经通过Spring Integration流将test/下的所有文本文件下载到本地目录，现在需要在文件下载完成后，把远程FTP服务器上的这些文本文件移动到test/archive/子目录中。

我们尝试在handle()方法中实现该操作，代码如下：

@Bean
public IntegrationFlow integrationFlow() {

    File localDirectory = new File("tmp/");

    FtpInboundChannelAdapterSpec ftpInboundChannelAdapterSpec = Ftp.inboundAdapter(gimmeFactory())
            .remoteDirectory("test/")
            .autoCreateLocalDirectory(true)
            .regexFilter(".*\\.txt$")
            .localDirectory(localDirectory)
            .preserveTimestamp(true)
            .remoteFileSeparator("/");

    return IntegrationFlows.from(ftpInboundChannelAdapterSpec, pc -> pc.poller(pm -> pm.fixedRate(1000, TimeUnit.MILLISECONDS)))
            .handle((file, messageHeaders) -> {
                messageHeaders.forEach((k, v) -> System.out.println(k + ':' + v));
                return null;
            })
            .handle(Ftp.outboundGateway(gimmeFactory(), AbstractRemoteFileOutboundGateway.Command.MV, "'test/archive'"))
            .get();

}

但执行后，远程文件并未移动到test/archive/目录中。请问如何修复上述代码，或者提供其他可行的实现方案？

更新：问题已解决 #

感谢指导，通过以下代码实现了需求：

@Bean
public IntegrationFlow integrationFlow() {            
    File localDirectory = new File("tmp/");
    FtpInboundChannelAdapterSpec ftpInboundChannelAdapterSpec = Ftp.inboundAdapter(gimmeFactory())
            .remoteDirectory("test/")
            .autoCreateLocalDirectory(true)
            .regexFilter(".*\\.txt$")
            .localDirectory(localDirectory)
            .preserveTimestamp(true)
            .remoteFileSeparator("/");
    
    return IntegrationFlows
            .from(ftpInboundChannelAdapterSpec, e -> e.poller(Pollers.fixedDelay(Duration.ofSeconds(5))))
            .handle(Ftp.outboundGateway(gimmeFactory(), AbstractRemoteFileOutboundGateway.Command.LS, "'test/'")
                    .options(AbstractRemoteFileOutboundGateway.Option.NAME_ONLY))
            .split()
            .handle(Ftp.outboundGateway(gimmeFactory(), AbstractRemoteFileOutboundGateway.Command.MV, "'test/' + payload").renameExpression("'test/archive/' + payload"))
            .channel("nullChannel")
            .get();
}

内容的提问来源于stack exchange，提问作者Wolf17