In Spark 1.5.2 I had a job that reads from textFile and saves some data into a Parquet table. One value was of type `ArrayList<String>` being successfully saved as an "array<string>" column in the Parquet table. I upgraded to Spark version 2.0.1, I changed the necessary code (SparkConf to SparkSession, DataFrame to Dataset) so no syntactic issues in the code. However, the job is not finishing anymore. The following exception is fired: `java.lang.RuntimeException: Error while encoding: java.lang.RuntimeException: java.util.ArrayList is not a valid external type for schema of array<string>`
at the line: `table.write().parquet(table_name);` I inspected the schema and it looked fine. Here is the string array column: `StructType(StructField(array_column,ArrayType(StringType,true),true)` ...and the value to be saved therein looks like: [aaa, bbb, ccc] The column array<string> is constructed this way: `DataTypes.createStructField(column, DataTypes.createArrayType(DataTypes.StringType, true), true);` I guess I provided all necessary code, but if more helps, please let me know. So there should be some logic-change in the latest version altering the possibility to save ArrayList<String> in an array of string in Parquet tables. Any help on solving/working around this would be very appreciated. *Regards, Grüße, **Cordialement,** Recuerdos, Saluti, προσρήσεις, 问候, تحياتي.* *Mohamed Nadjib Mami* *PhD Student - EIS Department - **Bonn University (Germany).* *About me! <http://www.strikingly.com/mohamed-nadjib-mami>* *LinkedIn <http://fr.linkedin.com/in/mohamednadjibmami/>*