Hi Vishwas,
You should pay attention to the other args.
The constructor provided by you has a `KeyedSerializationSchema` arg, while
the comments of the constructor which made you confused only has a
`SerializationSchema` arg. That's their difference.
Best,
Vino
Vishwas Siravara <vsirav...@gmail.com> 于2019年11月6日周三 上午9:16写道：
> Hi all,
> I am using flink 1.7.0 and using this constructor
>
> FlinkKafkaProducer(String topicId, KeyedSerializationSchema<IN>
> serializationSchema, Properties producerConfig)
>
> From the doc it says this constructor uses fixed partitioner. I want to
> partition based on key , so I tried to use this
>
> public FlinkKafkaProducer(
> String defaultTopicId,
> KeyedSerializationSchema<IN> serializationSchema,
> Properties producerConfig,
> Optional<FlinkKafkaPartitioner<IN>> customPartitioner)
>
> What should I pass in the optional field ? From the doc it says
>
> @param customPartitioner A serializable partitioner for assigning messages to
> Kafka partitions.
> * If a partitioner is not provided, records will be
> partitioned by the key of each record
> * (determined by {@link
> KeyedSerializationSchema#serializeKey(Object)}). If the keys
> * are {@code null}, then records will be distributed
> to Kafka partitions in a
> * round-robin fashion.
>
> This is super confusing(contradicting in a way) since the previous
> constructor says that fixedpartitioner will be used if customPartioner is
> not present.
>
> Best,
> Vishwas
>
