Java ZipEntry bug on Windows

I rolled out the Clearfox plugin on the Jive Software Community site a couple weeks ago and got some good feedback and some bad feedback. A number of people said they tried to install the Firefox part of the plugin, restarted Firefox and then didn’t see the Clearspace icon like my screenshots / screencast showed. There were no errors in the Clearspace error logs and no errors showed up in the Firefox JavaScript debug console. Through the help of a couple customers, I was able to narrow it down to running Clearspace on Windows: for some reason the zip file (really the XPI file) that the Clearfox plugin creates on the fly was invalid, at least according to Firefox. If you opened the XPI file using any common zip file utility the contents appeared to fine. As always, google came to the rescue and pointed me to this bug filed on bugs.sun.com, which has two parts. The Unicode file name bug didn’t matter to me, but this one did:

Within a ZIP file, pathnames use the forward slash / as separator, as required by the ZIP spec. This requires a conversion from or to the local file.separator on systems like Windows. The API (ZipEntry) does not take care of the transformation, and the need for the programmer to deal with it is not documented.

which wouldn’t hurt so much if it hadn’t been filed back in… get this… 1999. Are you kidding me?

Anyway, long story short: if you’re writing Java, creating a zip file that has paths while on a Windows based machine and deploying said zip file to a place that actually cares about the zip file specification (or violates Postel’s Law), then make sure to do something like this in your Java code:

String zipFilePath = file.getPath();
if (File.separatorChar != '/') {
  zipFilePath = zipFilePath.replace('\\', '/');
}
ZipEntry zipAdd = new ZipEntry(zipFilePath);

noting that even the workaround they give in the aforementioned bug is incorrect because they show

... file.getName();

which doesn’t contain the path separators. Awesome.

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