RFR - 8132734: java.util.jar.* changes to support multi-release jar files

Steve Drach steve.drach at oracle.com
Fri Oct 2 15:14:52 UTC 2015

>> To elaborate a bit, the implementation is quite straight forward.  ZipFileSystem builds an Inode tree on open.  That tree is implemented as a Map<Inode,Inode>.  For regular zip/jar files both the key and the value are the same Inode.  For multi-release jar files the value is the Inode of the appropriate versioned entry.  Configuration is through the Map<String,?> env parameter to the FileSystems.newFileSystem parameter.
> It sounds like you have a handle on this, the main thing is that by default it's just a file system, irrespective of whether META-INF/versions exists or not.


> If there is configuration specified via the env map then it can work multi-versioned, it just can't be the default because the file system provider has no knowledge as to how the API is being used.

Yes.  one has to specially request multi-release processing when the file system is opened.

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