Gradle automated build number incrementing

buildnumber.gradle

def versionFile = file('version.properties')
ext.buildnum = new Properties([BUILD_NUMBER: "0"]);
if (versionFile.isFile()) {
    versionFile.withReader { buildnum.load(it) }
}
def buildNumber = Integer.toString(Integer.parseInt(buildnum.BUILD_NUMBER) + 1)
buildnum.BUILD_NUMBER = buildNumber

task('saveBuildNumber') << {
    versionFile.withWriter { buildnum.store(it, "Automated build number increase") }
}

tasks.whenTaskAdded { task ->
    if (task.name == 'build') {
        task.dependsOn 'saveBuildNumber'
    }
}

version.properties

#Automated build number increase
#Thu Jul 05 19:21:05 CDT 2018
BUILD_NUMBER=1

In Line 9, << operator has been deprecated in gradle 4.0, so please replace it with doLast(Ref. https://stackoverflow.com/questions/55793095/could-not-find-method-leftshift-for-arguments-after-updating-studio-3-4)

Also, it would be nice if you add the way to read the values in build.gradle

Thanks for sharing :)