如何将arraylist转换为元组？

Question

: org.apache.spark.SparkException: Job aborted due to stage failure: Task 0 in stage 5.0 failed 1 times, most recent failure: Lost task 0.0 in stage 5.0 (TID 5, localhost): org.apache.spark.SparkException: Data of type java.util.ArrayList cannot be used

My rdd was made from an avro file that contains a key "mylist". How do I change this such that it uses a tuple of tuples instead? Is there a way to create a new RDD but convert that current arraylist of maps to a tuple of tuple of maps instead of arraylist of maps?

ie instead of [{"a":"vala", "a1":"vala1"},{"b":"valb", "b1":"valb1"}] , change it to (({"a":"vala", "a1":"vala1"},{"b":"valb","b1":"valb1"}))

Answer 1

You should just be able to call tuple on your list:

>>> tuple([{"a":"vala", "a1":"vala1"},{"b":"valb", "b1":"valb1"}])
({'a': 'vala', 'a1': 'vala1'}, {'b1': 'valb1', 'b': 'valb'})