Hi Mohit,
I don’t completely understand your question, but I’m assuming that you know the
type of records your custom sink will be receiving, but you don’t know how to
extract values from the records.
Assume that the type of the incoming records will be `Tuple2<String, Integer>`.
When writing your custom sink, you should define that type by:
```
public class YourCustomSink implements SinkFunction<Tuple2<String, Integer>> {
…
public void invoke(Tuple2<String, Integer> next) {
// use next.f0 / next.f1 to retrieve values from the tuple
}
...
}
```
You can of course also define generic types to replace `String` and `Integer`,
like so:
```
public class YourCustomSink<F, S> implements SinkFunction<Tuple2<F, S>> {
…
public void invoke(Tuple2<F, S> next) {
F field1 = next.f0;
S field2 = next.f1;
...
}
...
}
```
Just replace the generic types with concrete types when instantiating your
custom sink, according to your topology.
Let me know if this answers your question!
Cheers,
Gordon
On February 24, 2017 at 10:42:33 AM, 刘彪 ([email protected]) wrote:
Currently, OutputFormat is used for DataSet, SinkFunction is used for
DataStream. Maybe I misunderstand your problem. That will be better if you give
more details.
2017-02-24 5:21 GMT+08:00 Mohit Anchlia <[email protected]>:
This works for Kafka but for the other types of sink am I supposed to use some
type of outputformat?
On Tue, Feb 21, 2017 at 7:13 PM, 刘彪 <[email protected]> wrote:
Hi
I think there is a good way in FlinkKafkaProducerBase.java to deal with this
situation. There is a KeyedSerializationSchema user have to implement.
KeyedSerializationSchema will be used to serialize data, so that SinkFunction
just need to understand the type after serialization.
In your case, I think you can add a SerializationSchema interface in
SinkFunction. And user have to implement the SerializationSchema, maybe named
Tuple2SerializationSchema.
2017-02-22 7:17 GMT+08:00 Mohit Anchlia <[email protected]>:
What's the best way to retrieve both the values in Tuple2 inside a custom sink
given that the type is not known inside the sink function?
