[MSHADE-378] Shade plugin changes the compression level of nested jar entries

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.3.0
• Assignee: Romain Manni-Bucau
• Reporter: jeremy yu
• Created: 07/Oct/20 09:46
• Updated: 02/Apr/22 19:18
• Resolved: 02/Apr/22 19:18

Description

I'm trying to shade a part of dependencies from a flat jar which contains many nested jars. However, after shading, the nested jars can't be loaded in JVM and an exception is thrown:  "Exception in thread "main" java.lang.IllegalStateException: Unable to open nested entry 'xxx/xxxxx.jar'.It has been compressed and nested jar files must be stored without compression. Please check the mechanism used to create your executable jar file"

The reseaon of the above case is that shade plugin loses the meta information of orignal jar entries when copying nested jar (see DefaultShade#addResource method). 

I am happy to submit a fix for this, but I am not so sure about my solution. I would appreciate if someone can review my fix and give me guidance.

Issue Links

• breaks: MSHADE-417 Fix null bytes appended to small files by maven-shade-plugin
• links to: GitHub Pull Request #73