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AlBlue’s Blog

Macs, Modularity and More

Pack200 coming along nicely

Java 2006 Harmony Pack200

Working on the train today, I managed to get the Pack200 implementation unpacking a packed archive completely today. Admittedly, it wasn't a particularly interesting file:

public interface Test {

Believe it or not, this translates into 89 byte class file, which then gets archived into a 222 byte Jar file, and then into a 63 byte Pack200 file. So I've managed to decompress 63 bytes into the data needed to reconstitute the original .class file (though as yet, I've not weaved the bytes back together). I started doing this in July this year, so four months to uncompress 63 bytes ... that's an average of about 2 bytes/day :-)

Still, now I've got to a stage where I can decompress a file like this, it should be a matter of moving forwards and starting to decompress the other attribute types such as bytecodes, paramater annotations etc. Hopefully it won't take another four months to re-create the 222 byte Jar file ...