Replace a global library with a new version in Grails - grails

Question

Grails comes with Protobuf 2.4.1 as a 'global dependency', but my app uses a library that compiled against Protobuf 2.5.0 (and version 2.5.0 isn't compatible with 2.4.1).
The problem that I don't see any way to tell Grails to use only specified version instead of bundled. If I exclude it in BuildConfig it just excluded from application, all versions. I mean:
inherits("global") {
excludes 'protobuf-java'
}
dependencies {
//build 'com.google.protobuf:protobuf-java:2.5.0'
// or
compile 'com.google.protobuf:protobuf-java:2.5.0'
}
Grails fails with:
Fatal error during compilation org.apache.tools.ant.BuildException:
java.lang.NoClassDefFoundError: com/google/protobuf/MessageOrBuilder
How I can exclude global library, and add it as a new dependency instead? I'm using Grails 2.2.2

Answer 1

You do not need to exclude protobuf-java. The newest version, when provided as a dependency, should evict the older one. So v2.4.1 will be evicted by v2.5.0.
inherits("global") {
//excludes 'protobuf-java'
}
dependencies {
build 'com.google.protobuf:protobuf-java:2.5.0'
}
The above should be good. To witness the same, run a dependency-report on the grails app and look for the dependency.
To support with facts, I tested it and it works perfectly for me.
import com.google.protobuf.TextFormat
//Just to replicate your issue, but it did not complain about this import.
import com.google.protobuf.MessageOrBuilder
class BootStrap {
def init = { servletContext ->
TextFormat t = new TextFormat()
println t
}
def destroy = {
}
}
//Prints:
com.google.protobuf.TextFormat#372688e8