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https://issues.apache.org/jira/browse/IO-279?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17631266#comment-17631266
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Hieu Nguyen commented on IO-279:
--------------------------------

Is there a progress on fixing this issue? I still encounter this problem.

> Tailer erroneously considers file as new
> ----------------------------------------
>
>                 Key: IO-279
>                 URL: https://issues.apache.org/jira/browse/IO-279
>             Project: Commons IO
>          Issue Type: Bug
>    Affects Versions: 2.0.1, 2.4
>            Reporter: Sergio Bossa
>            Priority: Major
>         Attachments: IO-279.patch, disable_resetting.patch, fix-tailer.patch, 
> modify-test-fixed.patch, modify-test.patch
>
>          Time Spent: 1h
>  Remaining Estimate: 0h
>
> Tailer sometimes erroneously considers the tailed file as new, forcing a 
> repositioning at the start of the file: I'm still unable to reproduce this in 
> a test case, because it only happens to me with huge log files during Apache 
> Tomcat startup.
> This is the piece of code causing the problem:
> {code}
> // See if the file needs to be read again
> if (length > position) {
>     // The file has more content than it did last time
>     last = System.currentTimeMillis();
>     position = readLines(reader);
> } else if (FileUtils.isFileNewer(file, last)) {
>     /* This can happen if the file is truncated or overwritten
>         * with the exact same length of information. In cases like
>         * this, the file position needs to be reset
>         */
>     position = 0;
>     reader.seek(position); // cannot be null here
>     // Now we can read new lines
>     last = System.currentTimeMillis();
>     position = readLines(reader);
> }
> {code}
> What probably happens is that the new file content is about to be written on 
> disk, the date is already updated but content is still not flushed, so actual 
> length is untouched and there you go.
> In other words, I think there should be some better method to verify the 
> condition above, rather than relying only on dates: keeping and comparing the 
> hash code of the latest line may be a solution, but may hurt performances ... 
> other ideas?



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