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vasia / gelly-streaming

An experimental Graph Streaming API for Apache Flink
Apache License 2.0
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Run-time error while running connected components example #11

Closed Zainab-Abbas closed 8 years ago

Zainab-Abbas commented 8 years ago

Error:

Exception in thread "main" org.apache.flink.api.common.functions.InvalidTypesException: The return type of function 'run(WindowGraphAggregation.java:59)' could not be determined automatically, due to type erasure. You can give type information hints by using the returns(...) method on the result of the transformation call, or by letting your function implement the 'ResultTypeQueryable' interface. at org.apache.flink.streaming.api.transformations.StreamTransformation.getOutputType(StreamTransformation.java:211) at org.apache.flink.streaming.api.datastream.DataStream.getType(DataStream.java:139) at org.apache.flink.streaming.api.datastream.DataStream.flatMap(DataStream.java:575) at org.apache.flink.graph.streaming.WindowGraphAggregation.run(WindowGraphAggregation.java:59) at org.apache.flink.graph.streaming.SimpleEdgeStream.aggregate(SimpleEdgeStream.java:105) at org.apache.flink.graph.streaming.example.ConnectedComponents.main(ConnectedComponents.java:62) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:497) at com.intellij.rt.execution.application.AppMain.main(AppMain.java:144) Caused by: org.apache.flink.api.common.functions.InvalidTypesException: The types of the interface org.apache.flink.api.common.functions.FoldFunction could not be inferred. Support for synthetic interfaces, lambdas, and generic or raw types is limited at this point at org.apache.flink.api.java.typeutils.TypeExtractor.getParameterType(TypeExtractor.java:708) at org.apache.flink.api.java.typeutils.TypeExtractor.privateCreateTypeInfo(TypeExtractor.java:366) at org.apache.flink.api.java.typeutils.TypeExtractor.createTypeInfo(TypeExtractor.java:346) at org.apache.flink.graph.streaming.WindowGraphAggregation$PartialAgg.getProducedType(WindowGraphAggregation.java:99) at org.apache.flink.api.java.typeutils.TypeExtractor.getUnaryOperatorReturnType(TypeExtractor.java:278) at org.apache.flink.api.java.typeutils.TypeExtractor.getFoldReturnTypes(TypeExtractor.java:131) at org.apache.flink.streaming.api.datastream.WindowedStream.fold(WindowedStream.java:193) ... 8 more

vasia commented 8 years ago

Hey @Zainab-Abbas,

I cannot reproduce this. Can you give us some details on how you're trying to run the example? In your IDE or from the command line? Do you give input or you use default arguments?

Thanks!

Zainab-Abbas commented 8 years ago

if i do not give any parameters it takes the default ones right ?

vasia commented 8 years ago

I found the cause of the error and I'll push a fix. Thanks @Zainab-Abbas!

senorcarbone commented 8 years ago

good catch!