[gui] GUI Application fails to launch if ran from a Unicode path

[RainbowHype123]

Issue details

If you run the application when the path contains a Unicode character (such as the 🌐 emoji), the following error messages will be produced: "Java Virtual Machine Launcher - Error: A JNI error has occurred, please check your installation and try again" and "Java Virtual Machine Launcher - A Java Exception has occurred".

If this can't be fully patched, I would at least appreciate if there was a more explicit error message explaining to move the folder containing the app into a directory that doesn't contain a Unicode path.

Jadx version

1.5.6

Java version

25.0.3

OS

• Windows
• Linux
• macOS

[jpstotz]

I guess you start Jadx-Gui using the .exe file?

This exe file is generated using Launch4j and the error message is also defined in Launch4J so I don't think we can change it.

[RainbowHype123]

Yes, I was starting it with the .exe file. Unfortunate to hear that it might not be fixable. I think it would help if there was a small note somewhere, at least. (Maybe inside the jadx-gui section of the troubleshooting page?)

[jpstotz]

launch4j is a "very mature" project (the changelog covers more than 20 years). My guess is that for compatibility with old Windows versions internally launch4j still uses single byte character strings and correspondent Windows API methods. Thus can't handle "unicode" (multi-byte / UTF-16) characters at all. Windows doesn't use UTF-8 in it's API methods, so there is no alternative.

The only alternative would be using jpackage. @skylot has just recently added an option to build an msi file, it also seem to use a different exe launcher. You can download and try the latest unstable msi version here: https://nightly.link/skylot/jadx/workflows/build-artifacts/master