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Timo Walther commented on FLINK-3563: ------------------------------------- [~chobeat] can you check if https://github.com/apache/flink/pull/1759 solves you issues? > .returns() doesn't compile when using .map() with a custom MapFunction > ---------------------------------------------------------------------- > > Key: FLINK-3563 > URL: https://issues.apache.org/jira/browse/FLINK-3563 > Project: Flink > Issue Type: Bug > Components: Type Serialization System > Affects Versions: 0.10.1 > Reporter: Simone Robutti > Assignee: Timo Walther > Priority: Minor > > Defined a DummyMapFunction that goes from a java Map to another java Map like > this: > {code:title=DummyMapFunction.scalaborderStyle=solid} > class DummyMapFunction() extends MapFunction[java.util.Map[String, Any], > java.util.Map[FieldName, Any]] { > override def map(input: java.util.Map[String, Any]): > java.util.Map[FieldName, Any] = { > val result: java.util.Map[FieldName, Any] = new > java.util.HashMap[FieldName, Any]() > result > } > } > {code} > and trying to use it with a map: > {code:title=Main.java} > DummyMapFunction operator = new DummyMapFunction(); > DataSource<Map<String, Object>> dataset = env.fromCollection(input); > List<java.util.Map<FieldName, Object>> collectedResult = > dataset.map(operator).returns(java.util.Map.class).collect(); > {code} > the returns call doesn't compile because it can't resolve the returns method > with the parameter. > But if insted of creating a variable of type DummyMapFunction I create a > {code} > MapFunction operator=new DummyMapFuction(); > {code} > or I explicitly cast the variable to a MapFunction, it compiles and work > flawlessly. > This is a trick that works but I think is an unexpected behaviour. -- This message was sent by Atlassian JIRA (v6.3.4#6332)