gradle.wrapper nail version for gradle and java

wrapper.nail.java.gradle

allprojects {
    sourceCompatibility = JavaVersion.VERSION_1_8
    
    tasks.withType(JavaCompile) { task ->
        // nicify "invalid source release: 1.8" message:
        task.doFirst {
            if (("$System.env.JAVA_HOME".trim().isEmpty() || System.env.JAVA_HOME == null) && ("$System.env.JDK_HOME".trim().isEmpty() || System.env.JDK_HOME == null)) {
                println ' WARNING: neither JAVA_HOME nor JDK_HOME set!'
            }
            if (!JavaVersion.current().equals(project.sourceCompatibility)) {
                throw new IllegalStateException('Must be built with Java 8 or higher, is: ' + JavaVersion.current() + "\n (JAVA_HOME=\"$System.env.JAVA_HOME\")")
            }
        }
        task.options.encoding = 'UTF-8'
    }
}

wrapper.nail.version.gradle

def checkGradleVersionMatchesProjectDefinition() {
    if (gradle.gradleVersion != wrapper.gradleVersion) {
        throw new IllegalStateException('You are running this with gradle : ' + gradle.gradleVersion + " but it is set up with gradle wrapper " + wrapper.gradleVersion + ". PLEASE check usage of wrapper instead of local installed gradle!")
    }
}

allprojects {
    wrapper {
        gradleVersion = '2.11'
    }

    defaultTasks 'clean', 'build'

    clean.doFirst { checkGradleVersionMatchesProjectDefinition() }
    build.doFirst { checkGradleVersionMatchesProjectDefinition() }
    
    tasks.withType(JavaCompile) { task ->
        task.doFirst {
            checkGradleVersionMatchesProjectDefinition()
    }
}