TODO
public final class JavaSparkPi {
public static void main(String[] args) throws Exception {
SparkSession spark = SparkSession
.builder()
.appName("JavaSparkPi")
.getOrCreate();
JavaSparkContext jsc = new JavaSparkContext(spark.sparkContext());
int slices = (args.length == 1) ? Integer.parseInt(args[0]) : 2;
int n = 100000 * slices;
List<Integer> l = new ArrayList<>(n);
for (int i = 0; i < n; i++) {
l.add(i);
}
JavaRDD<Integer> dataSet = jsc.parallelize(l, slices);
int count = dataSet.map(integer -> {
double x = Math.random() * 2 - 1;
double y = Math.random() * 2 - 1;
return (x * x + y * y <= 1) ? 1 : 0;
}).reduce((integer, integer2) -> integer + integer2);
System.out.println("Pi is roughly " + 4.0 * count / n);
spark.stop();
}