Gradle Jacoco Exclude packages/classes

Help/Discuss
1

I have multi-module gradle build. I want to generate aggregated view of Code Coverage across modules.

subprojects {
    apply plugin: 'java'

    dependencies { compile 'org.jacoco:org.jacoco.ant:0.7.5.201505241946' }

    jacocoTestReport {
        additionalSourceDirs = files(sourceSets.main.allSource.srcDirs)
        sourceDirectories = files(sourceSets.main.allSource.srcDirs)
        //classDirectories =  files(sourceSets.main.output)
		afterEvaluate {
			classDirectories =  files(classDirectories.files.collect {
				fileTree(dir: it, exclude: 'net/xxxxx/test/core')
			})  //this task is excluding the core package classes
		}
		
		reports {
			html.enabled = true
			xml.enabled = false
			csv.enabled = false
			html.destination "${buildDir}/jacocoHtml"
		}
    }
}

task jacocoRootReport(type: org.gradle.testing.jacoco.tasks.JacocoReport) {
    dependsOn = subprojects.test
    additionalSourceDirs = files(subprojects.sourceSets.main.allSource.srcDirs)
    sourceDirectories = files(subprojects.sourceSets.main.allSource.srcDirs)
	classDirectories =  files(subprojects.sourceSets.main.output)
    executionData = files(subprojects.jacocoTestReport.executionData)
   
    reports {
        html.enabled = true
        xml.enabled = false
        csv.enabled = false
		html.destination "${buildDir}/jacocoHtml"
    }
} //however Root Report is not excluding the same.

Please let me know how do I exclude classes from Root/Aggregated report.