Meson should not (try to) modify jarfiles

[rom1v]

Commit c70a051 modify jar files to remove Class-Path entry from its manifest.

In scrcpy, an application composed of an Android "application" and a desktop application, I provide a prebuilt server as a jar file, so that users may build the application (the client part) without setting a whole Android build environment.

This jarfile is the Android "application" in itself, it is not a build dependency of the client app.

As a consequence of meson trying to modify the jar file, building scrcpy requires the jar executable, hence the whole openjdk-8-jdk package: Genymobile/scrcpy#404 (comment).

This is a useless annoyance, even if the problem is quite harmless.

In addition, in theory, such a .jar could require a Class-Path entry, and removing it would break its expected behavior.

So IMO, meson should not modify jarfiles.

[rom1v]

cc @noverby

[noverby]

My original commit did not change the jar file: #3736

[jpakkane]

You can set a custom classpath with the install_rpath entry. For jars it is interpreted as the classpath.

[rom1v]

So IMO, meson should not modify jarfiles.

Do you agree with this?

@jpakkane I'm not sure to understand what you suggested.

[jpakkane]

Looking through the code it seems that the problem is that Meson changes the jar classpath even if it has not built the jar itself with the jar command. Is this correct? If yes, then that is a bug, we should only modify jarfiles we build ourselves.