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Job return type problem of livy

Job return type problem of livy

Rising Star

I am working on submitting spl query via livy. And now I have the following questions:

1. The Job return type problem. When I set Integer or Double as Job returning type , it works well. But if I change return data type to something like List<String>, it throw the following error:

java.nullPointerException
at ...JobHandleImpl.get...
caused by: java.langu.NullPointerException
at java.util.Array$ArrayList.size(Arrays.java:3818)
at java.util.AbstractList.add
at org.apache.livy.shaded.kryo.kryo.serializers.CollectionSerializer.read

2. In sample code, it contains

System.err.printf("Uploading %s to the Spark context...\n", piJar);
  client.uploadJar(new File(piJar)).get();

I want to know do I have to use uploadJar or addJar method here? What I need is to running some spark code like in zeppelin or Hue. But in this step it seems need I to compile my spark code firstly and submit the jar.