Using NIO2 for writing zip file entries without corresponding folder entries

Alan Bateman Alan.Bateman at
Wed Oct 10 12:58:56 UTC 2018

On 10/10/2018 13:00, Rafael Winterhalter wrote:
> You are right with that it does emulate missing folders in the source 
> file.
> I have a use case where I patch a zip file with some additional 
> entries that are placed in directories of files that already exist in 
> the zip file. To do so, I have to add the directories for the added files.
I just tried a quick test with a zip file containing one entry x/foo.txt 
(created with zip -D to not create directory entries). With the zip file 
system then I replaced x/foo.txt, then a second test to create x/bar.txt 
and I didn't see any issues. Is that close to what you are doing? I 
suspect most usages of the zip file system provider are read-only (javac 
being the biggest user) and it's possible there are issues or short 
comings when writing or updating that haven't come up. If you can 
provides the instructions or a simple test case to show what you are 
seeing then it would be useful. Also which JDK release is this?

> Doing so confuses the processing backend which does not filter the 
> folder entries but treats them as normal files which causes this 
> processor to crash when treating them as regular files.
This sounds like a bug in whatever this system is as many zip tools will 
create directory entries by default.


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