Gradle task replace string in .java file

Question

I want to replace few lines in my Config.java file before the code gets compiled. All I was able to find is to parse file through filter during copying it. As soon as I have

Answer 1

To complement lance-java's answer, I found this idiom more simple if there's only one value you are looking to change:

task generateSources(type: Copy) {
    from 'src/replaceme/java'
    into "$buildDir/generated-src"
    filter { line -> line.replaceAll('xxx', 'aaa') }
}

Caveat: Keep in mind that the Copy task will only run if the source files change. If you want your replacement to happen based on other conditions, you need to use Gradle's incremental build features to specify that.