foreach() operation is an action.
> It do not return any value.
> It executes input function on each element of an RDD.
From :
http://data-flair.training/blogs/rdd-transformations-actions-apis-apache-spark/#39_Foreach
It executes the function on each item in RDD. It is good for writing database or publishing to web services. It executes parameter less function for each data items.
Example:
val mydata = Array(1,2,3,4,5,6,7,8,9,10)
val rdd1 = sc.parallelize(mydata)
rdd1.foreach{x=>println(x)}
OR
rdd1.foreach{println}
Output:
1
2
3
4
5
6
7
8
9
10