Re: Applying an void function to DataStream

[Timo Walther]

In your case a FlatMapFunction is better suited because it allows 0, 1 
or more output.


It would look like this:

text.flatMap((FlatMapFunction) (value, out) ->parse(value));


Or with an anonymous class:

text.flatMap(new FlatMapFunction() {
   @Override public void flatMap(String value, Collector out)throws 
Exception {
  parse(value); }
});


Regards,
Timo

Am 19.04.18 um 15:26 schrieb Soheil Pourbafrani:
parse function is a static function from another class I've imported 
into the project.


On Thu, Apr 19, 2018 at 5:55 PM, Soheil Pourbafrani 
> wrote:


Thanks,
my map code is like this:

stream.map(x -> parse(x));

I can't get what you mean!
Something like the line below?

DataStream t = stream.map(x -> parse(x));

?

On Thu, Apr 19, 2018 at 5:49 PM, Timo Walther > wrote:

Hi Soheil,

Flink supports the type "java.lang.Void" which you can use in
this case.

Regards,
Timo


Am 19.04.18 um 15:16 schrieb Soheil Pourbafrani:

Hi, I have a void function that takes a String, parse it
and write it into Cassandra (Using pure java, not Flink
Cassandra connector). Using Apache Flink Kafka connector,
I've got some data into DataStream. Now I want to
apply Parse function to each message in
DataStream, but as the Parse function returns
nothing (is void), I got the error
no instance of type variable R exists so that void
conforms to R

Is there any way to do such process using apache Flink?

Re: Applying an void function to DataStream

[Timo Walther]

Hi Soheil,

Flink supports the type "java.lang.Void" which you can use in this case.

Regards,
Timo


Am 19.04.18 um 15:16 schrieb Soheil Pourbafrani:
Hi, I have a void function that takes a String, parse it and write it 
into Cassandra (Using pure java, not Flink Cassandra connector). Using 
Apache Flink Kafka connector, I've got some data into 
DataStream. Now I want to apply Parse function to each message 
in DataStream, but as the Parse function returns nothing (is 
void), I got the error

no instance of type variable R exists so that void conforms to R

Is there any way to do such process using apache Flink?

Applying an void function to DataStream

[Soheil Pourbafrani]

Hi, I have a void function that takes a String, parse it and write it into
Cassandra (Using pure java, not Flink Cassandra connector). Using Apache
Flink Kafka connector, I've got some data into DataStream. Now I
want to apply Parse function to each message in DataStream, but as
the Parse function returns nothing (is void), I got the error
no instance of type variable R exists so that void conforms to R

Is there any way to do such process using apache Flink?