Good example of the merged Jacoco code covarage Gradle configuration

build.gradle

apply plugin: 'com.android.application'
apply from: "$rootDir/coverage.gradle"
//...

android {
//...

    buildTypes {
//...    
            debug {
                testCoverageEnabled true //we use "debug" build type for test coverage (can be other)
            }
    }
//...
    testOptions {
        unitTests.returnDefaultValues = true
        unitTests.all {
            jacoco {
                includeNoLocationClasses = true
            }
        }
    }
//...
}

coverage.gradle

apply plugin: 'jacoco'

/**
 * The correct path of the report is $rootProjectDir/app/build/reports/jacoco/index.html
 * to run this task use: ./gradlew clean jacocoTestReport
 */
task jacocoTestReport(type: JacocoReport, dependsOn: ['testDebugUnitTest', 'createDebugCoverageReport']) { //we use "debug" build type for test coverage (can be other)
    group = "reporting"
    description = "Generate unified Jacoco code coverage report"

    reports {
        xml.enabled = false
        html.enabled = true
        csv.enabled = false
        xml.destination = "${buildDir}/reports/jacocoTestReport.xml"
        html.destination = "${buildDir}/reports/jacoco"
        csv.destination = "${buildDir}/reports/jacocoTestReport.csv"
    }

    def fileFilter = [
            '**/*Test*.*',
            '**/AutoValue_*.*',
            '**/*JavascriptBridge.class',
            '**/R.class',
            '**/R$*.class',
            '**/Manifest*.*',
            'android/**/*.*',
            '**/BuildConfig.*',
            '**/*$ViewBinder*.*',
            '**/*$ViewInjector*.*',
            '**/Lambda$*.class',
            '**/Lambda.class',
            '**/*Lambda.class',
            '**/*Lambda*.class',
            '**/*$InjectAdapter.class',
            '**/*$ModuleAdapter.class',
            '**/*$ViewInjector*.class',
            '**/*_MembersInjector.class', //Dagger2 generated code
            '*/*_MembersInjector*.*', //Dagger2 generated code
            '**/*_*Factory*.*', //Dagger2 generated code
            '*/*Component*.*', //Dagger2 generated code
            '**/*Module*.*' //Dagger2 generated code
    ]
    def debugTree = fileTree(dir: "${buildDir}/intermediates/classes/debug", excludes: fileFilter) //we use "debug" build type for test coverage (can be other)
    def mainSrc = "${project.projectDir}/src/main/java"

    sourceDirectories = files([mainSrc])
    classDirectories = files([debugTree])
    executionData = fileTree(dir: "$buildDir", includes: [
            "jacoco/testDebugUnitTest.exec", //we use "debug" build type for test coverage (can be other)
            "outputs/code-coverage/connected/*coverage.ec"
    ])
}