Gradle Checkstyle with threshold of errors.

checkstyle.gradle

tasks.withType(Checkstyle).each { checkstyleTask ->
    checkstyleTask.doLast {
        reports.all { report ->
            def errors = 0
            def threshold = 1
            def outputFile = report.destination
            outputFile.text.eachLine {
                if (it.contains("<error ")) {
                    errors++
                }
            }
            if(errors >= threshold){
                throw new GradleException("There were checkstyle warnings! For more info check $outputFile")
            }
        }
    }
}