Android 3.x+ Java ZipFile Class - Can't read ZipEntries from big files

Question

If I open a big zip file (250MB) via the ZipFile class and try to read the entries. This works fine on 2.x in the emulator and real hardware. If I use the exact some code on my tablet (Asus Transformer running 4.0.3) or the emulator (3.2), I can't read any entries. The size() function of the ZipFile class always returns zero and the ZipFile does not return any zip entries. Even the a zip app that comes with the ROM on my tablet can't read any entries. The zip file is not damaged. I checked it.

The code to read from ZipFile works fine on all version with smaller zip files. What has changed between 2.x and 3.x/4.x??

My Testfile is the C64Music.zip from the HighVoltage Sid Collection. It contains over 40.000 files and is around 250MB.

I have no clue where to look at.

Answer 1

This is a known issue with the android ZipFile implementation:

http://code.google.com/p/android/issues/detail?id=23207

Basically zip files only support up to 65k entries. There is an extended version of the zip file format called Zip64, which supports a larger number of entries. Unfortunately ZipFile on android cannot read Zip64. You will probably find that the C64Music.zip file is in the Zip64 format

A work around is to use the Apache Commons Compress library instead of the native implementation. Their version of ZipFile supports Zip64: http://commons.apache.org/compress/apidocs/org/apache/commons/compress/archivers/zip/ZipFile.html