使用java、scala、python三种语言实现spark rdd的reduce算子的使用

Java:

JavaRDD<Integer> numbers = sc.parallelize(Arrays.asList(1, 2, 3, 4, 5));
int sum = numbers.reduce((a, b) -> a + b);
System.out.println(sum);

Scala:

val numbers = sc.parallelize(Seq(1, 2, 3, 4, 5))
val sum = numbers.reduce(_ + _)
println(sum)

Python:

numbers = sc.parallelize([1, 2, 3, 4, 5])
sum = numbers.reduce(lambda a, b: a + b)
print(sum)