Spring Integration custom processing order not working

Question

I have configured spring integration to poll a directory. I have configured InBoundChannelAdaptor with poller configuration of

maxMessagesPerPoll = -1 trigger = PeriodicTrigger(1000)

Also I have provided custom comparator while creating the FileReadingMessageSource, to process the files based on modification datetime.

    FileReadingMessageSource source = new FileReadingMessageSource(new Comparator<File>(){
    
    @Override
    public int compare(File a , File b)
    {
            if(a.lastModified() > b.lastModified())
            {
                   return 1;
            }else{
                    return -1;
            }
    }


})

My folder is having 2000 files, but files are not processing in the lastModified manner, means the oldest file should process first, but it is not happening.

We probably need to know more about your downstream processing. Perhaps you do some thread shifting over there breaking the mentioned order. — Artem Bilan, Dec 23 '21 at 13:31
As of now, doing nothing, just printing the filename to check. Also, if I remove the custom ordering, by default as per the Spring Docs, it processes in Natural Ordering of path, which is working perfectly fine. But what I want is file should get process in FIFO order instead of natural ordering of path. — Kshitiz, Dec 24 '21 at 05:31

score 1 · Answer 1 · answered Mar 04 '22 at 17:01

This works for me as expected:

@Bean
IntegrationFlow lastModifiedOrderFlow() {
    return IntegrationFlows.from(
                    Files.inboundAdapter(new File(System.getProperty("user.home") + "/Downloads"),
                            Comparator.comparingLong(File::lastModified)),
                    e -> e.poller(p -> p.fixedDelay(1000).maxMessagesPerPoll(-1)))
            .handle(m -> System.out.println(m.getPayload()))
            .get();
}

We probably need to know more about your setup.

Spring Integration custom processing order not working

1 Answers1