Andra Lungu created FLINK-2899: ---------------------------------- Summary: The groupReduceOn* methods which take types as a parameter fail with TypeErasure Key: FLINK-2899 URL: https://issues.apache.org/jira/browse/FLINK-2899 Project: Flink Issue Type: Bug Components: Gelly Affects Versions: 0.10 Reporter: Andra Lungu
I tried calling groupReduceOnEdges (EdgesFunctionWithVertexValue<K, VV, EV, T> edgesFunction, EdgeDirection direction, TypeInformation<T> typeInfo) in order to make the vertex-centric version of the Triangle Count library method applicable to any kind of key and I got a TypeErasure Exception. After doing a bit of debugging (see the hack in https://github.com/andralungu/flink/tree/trianglecount-vertexcentric), I saw that actually the call to TypeExtractor.createTypeInfo(NeighborsFunctionWithVertexValue.class, .... in ApplyNeighborCoGroupFunction does not work properly, i.e. it returns null. From what I see, the coGroup in groupReduceOnNeighbors tries to infer a type before "returns" is called. I may be missing something, but that particular feature (groupReduceOn with types) is not documented or tested so we would also need some tests for that. -- This message was sent by Atlassian JIRA (v6.3.4#6332)