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https://issues.apache.org/jira/browse/COMPRESS-508?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17073611#comment-17073611
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Stefan Bodewig commented on COMPRESS-508:
-----------------------------------------
{{ZipArchiveInputStream}} is designed to work from a single {{InputStream}} -
like all the other {{ArchiveInputStream}}s, something that is not seekable. In
this case reading the metadata and then accessing the streams is not an option.
If you are in a situation where you can read a stream more than once then this
is closer to a real random access case - and this is where {{ZipFile}} comes
into play.
??Why isn't there something similar to this???
Because nobody has written one? ;-)
Either the use case is not as common as you think or nobody has been bothered
enough to actually implement it. So far it is not something I have needed, for
example.
As to how you'd go about it. There are various traps you need to avoid.
{{InputStream.mark}} and {{seek}} are not reliable, so you have to be prepared
to use {{read}} in order to position the stream (you may be able to trust
{{skip}} but that's not always the case either) and be prepared to close the
stream and reopen a fresh one every time you go backwards. Unfortunately
finding the meta data (the central directory) in {{ZipFile}} involves searching
the stream backwards from the end of the stream, so this very first part will
be either extremely slow or you implement something smarter that "close, reopen
a new stream, reposition" with caches. I'm afraid this is only scratching the
surface.
> Bug: cannot get file size of ArchiveEntry using ZipArchiveInputStream
> ---------------------------------------------------------------------
>
> Key: COMPRESS-508
> URL: https://issues.apache.org/jira/browse/COMPRESS-508
> Project: Commons Compress
> Issue Type: Bug
> Components: Build
> Affects Versions: 1.20
> Environment: Android 9 and Android 10, on both emulator and real
> device .
> Reporter: AD_LB
> Priority: Major
> Attachments: 2020-03-31_20-53-36.png, 2020-04-01_18-28-19.mp4,
> ZipTest.zip, ZipTest2.zip, test.zip
>
>
> I'm trying to use ZipArchiveInputStream to iterate over the items of a zip
> file (which may or may not be a real file on the file-system, which is why I
> use a stream), optionally creating a stream from specific entries.
> One of the operations I need is to get the size of the files within.
> For some reason, it fails to do so. Not only that, but it throws an exception
> when I'm done with it:
> {code:java}
> Error:org.apache.commons.compress.archivers.zip.UnsupportedZipFeatureException:
> Unsupported feature data descriptor used in entry ...
> {code}
> I've attached here 3 files:sample project, the problematic zip file (remember
> that you need to put it in the correct path and grant storage permission),
> and a screenshot of the issue.
> Note that if I open the file using a third party PC app (such as
> [7-zip|https://www.7-zip.org/] ), it works fine, including showing the file
> size inside.
> Files:
> !2020-03-31_20-53-36.png![^test.zip]
> [^ZipTest.zip]
> Here's the relevant code (kotlin) :
>
> {code:java}
> thread {
> try {
> val file = File("/storage/emulated/0/test.zip")
> ZipArchiveInputStream(FileInputStream(file)).use {
> while (true) {
> val entry = it.nextEntry ?: break
> Log.d("AppLog", "entry:${entry.name} ${entry.size} ")
> }
> }
> Log.d("AppLog", "got archive ")
> } catch (e: Exception) {
> Log.d("AppLog", "Error:$e")
> e.printStackTrace()
> }
> }
> {code}
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