Spring Boot Integration SFTP and Google Cloud Storage

Question

Sorry for my poor English Grammar. I am working on projects where we need to upload data from SFTP Server to Google Cloud Storage using Spring Boot. SFTP Server is having data(file.txt) coming from many sensors on some particular time let says every 10 minutes.These text file we need to keep sync with Google Cloud Storage. Whenever a new file uploaded in SFTP Server it should be upload in Google Cloud Storage.I am using Spring SFTP integration.I am able to sync data from SFTP Server to Google Cloud Storage buckets.But I am not sure how to delete local temp files when file transferred to GCP Storage is complete for every files.Please find my codes below.(I have very basic knowledge about Spring.I am just using annotation to complete this task.) I found some url in stackoverflow and using.

Spring Integration SFTP Example with Spring Boot

package com.interiorclientapi.sftp;

import org.springframework.beans.factory.annotation.Autowired;
import java.io.File;
import org.springframework.cloud.gcp.storage.integration.GcsSessionFactory;
import org.springframework.cloud.gcp.storage.integration.outbound.GcsMessageHandler;
import org.springframework.context.annotation.Bean;
import org.springframework.integration.annotation.InboundChannelAdapter;
import org.springframework.integration.annotation.Poller;
import org.springframework.integration.annotation.ServiceActivator;
import org.springframework.integration.core.MessageSource;
import org.springframework.integration.expression.ValueExpression;
import org.springframework.integration.file.filters.AcceptOnceFileListFilter;
import org.springframework.integration.file.remote.session.CachingSessionFactory;
import org.springframework.integration.file.remote.session.SessionFactory;
import org.springframework.integration.sftp.inbound.SftpInboundFileSynchronizer;
import org.springframework.integration.sftp.inbound.SftpInboundFileSynchronizingMessageSource;
import org.springframework.integration.sftp.session.DefaultSftpSessionFactory;
import org.springframework.messaging.MessageHandler;
import org.springframework.stereotype.Component;

import com.google.cloud.storage.Storage;
import com.jcraft.jsch.ChannelSftp.LsEntry;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;


public class InteriorClientApiSFTP {

     @Autowired
     SFTPProperties sftpProperties;

     private static final Logger logger = LoggerFactory.getLogger(InteriorClientApiSFTP.class);

    @Bean
    public SessionFactory<LsEntry> sftpSessionFactory() {
        DefaultSftpSessionFactory factory = new DefaultSftpSessionFactory(true);
        String port = sftpProperties.getPort();
        factory.setHost(sftpProperties.getHost());
        factory.setPort(port!=null?Integer.parseInt(port):22);
        factory.setUser(sftpProperties.getsftpUsername());
        factory.setPassword(sftpProperties.getsftpPassword());
        factory.setAllowUnknownKeys(true);
        System.out.println("creating seession to sftp server");
        return new CachingSessionFactory<LsEntry>(factory);
    }

    @Bean
    public SftpInboundFileSynchronizer sftpInboundFileSynchronizer() {
        SftpInboundFileSynchronizer fileSynchronizer = new SftpInboundFileSynchronizer(sftpSessionFactory());
        fileSynchronizer.setDeleteRemoteFiles(false);
        fileSynchronizer.setRemoteDirectory(sftpProperties.getRemotedirectory());
       // fileSynchronizer.setFilter(new SftpSimplePatternFileListFilter("*.txt"));
        System.out.println("inside  sftpInboundFileSynchronizer");
        return fileSynchronizer;
    }


@Bean
@InboundChannelAdapter(channel = "mineChannel", poller = @Poller(fixedDelay = "5000"))
public MessageSource<File> sftpMessageSource() {
        SftpInboundFileSynchronizingMessageSource source = new SftpInboundFileSynchronizingMessageSource(
                sftpInboundFileSynchronizer());     
        source.setLocalDirectory(new File(sftpProperties.getLocaldirectory()));
        source.setAutoCreateLocalDirectory(true);
        source.setLocalFilter(new AcceptOnceFileListFilter<File>());
        System.out.println("inside  sftpMessageSource");
        return source;
    }

 @Bean
 @ServiceActivator(inputChannel = "mineChannel")
 public MessageHandler outboundChannelAdapter(Storage gcs) {
      GcsMessageHandler outboundChannelAdapter = new GcsMessageHandler(new GcsSessionFactory(gcs));    
      outboundChannelAdapter.setRemoteDirectoryExpression(new ValueExpression<>(sftpProperties.getGcpSFTPBucket())); 
      System.out.println("outboundChannelAdapter");
      return outboundChannelAdapter;
 } 

}