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https://issues.apache.org/jira/browse/COMPRESS-621?focusedWorklogId=831776&page=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-831776
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ASF GitHub Bot logged work on COMPRESS-621:
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Author: ASF GitHub Bot
Created on: 07/Dec/22 14:01
Start Date: 07/Dec/22 14:01
Worklog Time Spent: 10m
Work Description: Glavo opened a new pull request, #334:
URL: https://github.com/apache/commons-compress/pull/334
Since the zip central directory is at the file end, we can splice other
content before the zip file.
As an example, in Java 9 and above, the `$JAVA_HOME/jmods` folder contains
some files with the extension `jmod`.
The jmod file is a normal zip file, but the file starts with the four-byte
magic number `0x4A 0x4D 0x01 0x00`.
Another example, [Ammonite Shell](http://ammonite.io/) splices a bash shell
script before the jar file, looks for Java through the bash shell script and
starts itself.
`java.util.zip.ZipFile` reads these files correctly, but
`org.apache.commons.compress.archivers.zip.ZipFile` recognizes them as empty
zip files.
This PR fixes this issue and allows users to read content before the zip
body.
I didn't implement it for zip64 because `java.util.zip.ZipFile` didn't
implement it either, and I'm not sure how it should be implemented correctly.
(I seem to have missed the release date of commons-compress 1.22. This
problem has a wider impact, and I hope to fix it as soon as possible.)
Issue Time Tracking
-------------------
Worklog Id: (was: 831776)
Remaining Estimate: 0h
Time Spent: 10m
> ZipFile does not support prepending additional data to the zip content
> ----------------------------------------------------------------------
>
> Key: COMPRESS-621
> URL: https://issues.apache.org/jira/browse/COMPRESS-621
> Project: Commons Compress
> Issue Type: Bug
> Components: Archivers
> Affects Versions: 1.21
> Reporter: Glavo
> Priority: Major
> Time Spent: 10m
> Remaining Estimate: 0h
>
> In general, Zip files support placing arbitrary content before their body
> without affecting their compliance.
> Here is an example:
> [https://github.com/huanghongxun/HMCL/releases/download/v3.5.2.218/HMCL-3.5.2.218.exe]
>
> This is actually a jar file, but we prepend an exe launcher to it, so it can
> be used both as a jar and as an exe.
> java.util.zip.ZipFile can open and read it normally, but
> org.apache.commons.compress.archivers.zip.ZipFile can open it but cannot read
> any entries.
>
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