java - Using Unicode characters for file names inside a zip archive

Question

I am zipping a file name contains some special characters like Péréquation LES HOPITAUX NEUFS.xls to a different folder, say temp.

I am able to zip the file but the problem is the name of file is changing automatically to P+?r+?quation LES HOPITAUX NEUFS.xls.

How can I support unicode characters for file names inside a zip archive?

Answer 1

It depends a little bit on what code you're using to create the archive. The old Java compression classes are not so flexible as you need.

You may use Apache Commons Compress. Michael Simons wrote this nice piece of code:

ZipArchiveOutputStream ostream = ...; // Your initialization code here
ostream.setEncoding("Cp437"); // This should handle your "special" characters
ostream.setFallbackToUTF8(true); // For "unknown" characters!
ostream.setUseLanguageEncodingFlag(true);                               
ostream.setCreateUnicodeExtraFields(
    ZipArchiveOutputStream.UnicodeExtraFieldPolicy.NOT_ENCODEABLE);

If you're using Java 7 then you finally have a Charset parameter (that can be UTF-8) on the ZipOutputStream constructor

The big problem, anyway, is that many implementations don't understand Unicode encoding because original ZIP file format is ASCII and there is not an official standard for Unicode. See this post for further details.