Dear All,
I do not understand what the error in the following code can be?
Graph<GradoopId, Long, NullValue> gellyGraph = ...
Graph<GradoopId,Summarization.VertexValue<Long>,
Summarization.EdgeValue<NullValue>> g =
gellyGraph.run(new
Summarization<GradoopId, Long, NullValue>());
g.getVertices().print(); //this one works fine
g.getEdges().print(); //this one gives the following error
...
org.apache.flink.types.NullFieldException: Field 2 is null, but
expected to hold a value.
at
org.apache.flink.api.java.typeutils.runtime.TupleSerializer.serialize(TupleSerializer.java:126)
at
org.apache.flink.api.java.typeutils.runtime.TupleSerializer.serialize(TupleSerializer.java:30)
at
org.apache.flink.runtime.plugable.SerializationDelegate.write(SerializationDelegate.java:56)
at
org.apache.flink.runtime.io.network.api.serialization.SpanningRecordSerializer.addRecord(SpanningRecordSerializer.java:83)
at
org.apache.flink.runtime.io.network.api.writer.RecordWriter.emit(RecordWriter.java:85)
at
org.apache.flink.runtime.operators.shipping.OutputCollector.collect(OutputCollector.java:65)
at
org.apache.flink.runtime.operators.util.metrics.CountingCollector.collect(CountingCollector.java:35)
at
org.apache.flink.graph.library.Summarization$VertexGroupReducer.reduce(Summarization.java:318)
at
org.apache.flink.runtime.operators.GroupReduceDriver.run(GroupReduceDriver.java:131)
at org.apache.flink.runtime.operators.BatchTask.run(BatchTask.java:486)
at
org.apache.flink.runtime.operators.BatchTask.invoke(BatchTask.java:351)
at org.apache.flink.runtime.taskmanager.Task.run(Task.java:584)
at java.lang.Thread.run(Thread.java:748)
I also tried with different types for EdgeValue. The same error appears.
When I look at the result vertices, everything looks fine.
But the result edges has this problem.
Any idea?
Regards,
Ali
