Apache Flink: SpiltStream vs side outputs - apache-flink

Question

From this question, I understand that SplitStream in Apache Flink is now deprecated and it's recommended to use side-outputs instead.
Can someone give an example of how side-output can replace the splitStream?
e.g. How can the code snippet below be modified to use side-output?
DataStream mainDataStream = some definition
SplitStream<some-type> splitStream = mainDataStream.select("some-string")

Answer 1

Rather than
SplitStream<Integer> split = someDataStream.split(new OutputSelector<Integer>() {
#Override
public Iterable<String> select(Integer value) {
List<String> output = new ArrayList<String>();
if (value % 2 == 0) {
output.add("even");
}
else {
output.add("odd");
}
return output;
}
});
DataStream<Integer> evens = split.select("even");
DataStream<Integer> odds = split.select("odd");
you can now do
final OutputTag<Integer> evenTag = new OutputTag<String>("even"){};
final OutputTag<Integer> oddTag = new OutputTag<String>("odd"){};
SingleOutputStreamOperator<Integer> mainDataStream = someDataStream
.process(new ProcessFunction<Integer, Integer>() {
#Override
public void processElement(
Integer value,
Context ctx,
Collector<Integer> out) throws Exception {
if (value % 2 == 0) {
ctx.output(evenTag, value);
} else {
ctx.output(oddTag, value);
}
});
DataStream<Integer> evens = mainDataStream.getSideOutput(evenTag);
DataStream<Integer> odds = mainDataStream.getSideOutput(oddTag);
Note that, unlike split streams, the side output streams can be of different types.