public ConnectedStreams < IN1 , IN2 > keyBy ( int [ ] keyPositions1 , int [ ] keyPositions2 ) { return new ConnectedStreams <> ( environment , inputStream1 . keyBy ( keyPositions1 ) , inputStream2 . keyBy ( keyPositions2 ) ) ; }
KeyBy operation for connected data stream . Assigns keys to the elements of input1 and input2 according to keyPositions1 and keyPositions2 .