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

1. I definitely wouldn't overwrite the original file
2. I like to keep things directory based rather than filename based so if it were me, I'd put Config.java in it's own folder (eg src/replaceme/java)
3. I'd create a generated-src directory under $buildDir so it's deleted via the clean task.

You can use the Copy task and ReplaceTokens filter. Eg:

apply plugin: 'java'
task generateSources(type: Copy) {
    from 'src/replaceme/java'
    into "$buildDir/generated-src"
    filter(ReplaceTokens, tokens: [
        'xxx': 'aaa', 
        'yyy': 'bbb'
    ])
}
// the following lines are important to wire the task in with the compileJava task
compileJava.source "$buildDir/generated-src"
compileJava.dependsOn generateSources