A groovyfied version of GroovySparkPi

GroovySparkPi.groovy

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
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package org.apache.spark.examples

import groovy.transform.CompileStatic
import groovy.util.logging.Log
import org.apache.spark.SparkConf
import org.apache.spark.api.java.JavaSparkContext
import org.apache.spark.api.java.function.Function
import org.apache.spark.api.java.function.Function2

/**
 * Computes an approximation to pi
 * Usage: GroovySparkPi [slices]
 */
@CompileStatic
final class GroovySparkPi {

  static void main(String[] args) throws Exception {
    def sparkConf = new SparkConf().setAppName("GroovySparkPi")
    def jsc = new JavaSparkContext(sparkConf)

    int slices = (args.length == 1) ? Integer.parseInt(args[0]) : 2

    int n = 100000 * slices
    def dataSet = jsc.parallelize(0..<n, slices)

    def mapper = {
      double x = Math.random() * 2 - 1
      double y = Math.random() * 2 - 1
      return (x * x + y * y < 1) ? 1 : 0
    }

    int count = dataSet
            .map(mapper as Function<Integer, Integer>)
            .reduce({int a, int b -> a + b} as Function2<Integer, Integer, Integer>)

    println "Pi is roughly ${4.0 * count / n}"

    jsc.stop()
  }
}

OK. I've got the problem. The class must implement Serializable (obviously!). The other examples worked because it was just a static method (run).

AFAIK it is possible to specify the script superclass, but I don't remember how to do that.

For the records. It's enough to create a superclass of Script implementing Serializable and use the BaseScript annotation. An example here: