I don't any reason why the Scala approach should not work in Java. For example, the flink-graph API seems to be built on top of this concept (in Java):
https://github.com/project-flink/flink-graph/blob/master/src/main/java/flink/graphs/Graph.java 2015-01-27 23:45 GMT+01:00 Flavio Pompermaier <pomperma...@okkam.it>: > Hi Stephan, thanks for the response! Is that the only possibility?there's > no java alternative at the moment? > On Jan 27, 2015 10:23 PM, "Stephan Ewen" <se...@apache.org> wrote: > >> Hi Flavio! >> >> In Scala: >> >> You can do that, using the "pimp my library" pattern. Define your own >> data set (MyDataSet) that has the method "myFunction()" and define an >> implicit conversion from DataSet to MyData set. See here for more details: >> http://alvinalexander.com/scala/scala-2.10-implicit-class-example >> >> >> In Java >> >> 1) You need to define a class MyUtils, there >> >> public class MyUtils { >> public static DataSet[MyType] myFunction(DataSet[String] input) { >> return input.map(...).reduce(...); >> } >> } >> >> 2) You can define a custom unary operation: >> >> It allows you to write code like "DataSet<MyType> result = >> data.runOperation(new MyFunction()); >> >> public class MyFunction implements CustomUnaryOperation<String, MyType> { >> private DataSet<String> input; >> >> public void setInput(DataSet<String> input) { >> this.input = input >> } >> >> public DataSet<MyType> createResult() { >> return input.map(...).reduce(...); >> } >> } >> >> >> https://github.com/apache/flink/blob/master/flink-java/src/main/java/org/apache/flink/api/java/operators/CustomUnaryOperation.java >> >> Greetings, >> Stephan >> >> >> >> >> >> >> >> >> >> On Tue, Jan 27, 2015 at 5:37 AM, Flavio Pompermaier <pomperma...@okkam.it >> > wrote: >> >>> Hi guys, >>> >>> I'd like to know whether it is possible or not save a chain of operators >>> as a custom function. >>> For example, If I have a DataSet transformation composed by a map >>> followed by a reduce (but this is a simple case, I could have a more >>> complex scenario), is it possible to save it as a custom function (eg. >>> "myFunction" => map.reduce) so that I can call mydataset.myFunction() >>> instead of myDataset.map().reduce()? >>> >>> Best, >>> Flavio >>> >> >>
