Android gradle buildTypes: Duplicate class

Question

I'm converting my app to use gradle, and I'm trying to use the buildTypes. I have a Constants class which I wish to modify for my release build. So I have a file at src/main/java/my/package/name/Constants.java and at src/release/java/my/package/name/Constants.java.

When I try to build this, gradle tells me the build failed on the Constants file in my release buildtype, with the error that it's a duplicate class.

I also tried adding a different sourceSet for this in my build.gradle like this:

sourceSets {
    main {
        java.srcDirs = ['src/main/java'];
        //...
    }
    release {
        java.srcDirs = ['src/release/java'];
    }
}

But this still gives me the same error. So I'm wondering, what am I doing wrong here?

Superstition

Answer 1

You can not have a class in main and release. You need to split it into something like debug and release.

gradle will merge the source sets for each buildType with main.
This is the reason, why the class gets duplicated in your release build.

So the rule is: put a class into main, or in every buildType but not both.

Keldah

If one put class A in buildType paid and free, main complains about missing class A. How do one handle it? – Dumont

Documentation says it possible to override class with same package name and class name developer.android.com/tools/building/… but it's not working :( – Markup

Unless I'm missing something, the docs say that you can have same class with same class name/ package name if they are in different flavors. Not so if one is in main and another is in a flavor. – Dermot

@Dermot The docs here are clear about the flavors and duplicate classes. – Arthur

Use dynamic class loading and an interface to load the class if it exists on the flavor. – Indic

There are ways to replace the main sourceset(main dir) for different build types? – Blowzed

Answer 2

The answer from "fix" helped me on the way, but I got an error from the main Gradle, saying a constant was missing (in my class Config). This since I had my class only in paid and free version and not in main. Could not find the Config class. Im not sure if this is a bug in Studio... I finally solved it with the following:

buildTypes {

    release {
        ...
        buildConfig "public static final boolean XYZ = false;"
    }

}

And the instead of using my Config.XYZ class constant I used buildConfig.XYZ

Dumont

or just buildConfigField "boolean", "XYZ", "false" – Heintz