Hey Timo,
yes that is what I needed to know.
Thanks
- Michael
Am 12.08.2015 um 12:44 schrieb Timo Walther <twal...@apache.org>:
> Hello Michael,
>
> every time you code a Java program you should avoid object creation if you
> want an efficient program, because every created object needs to be garbage
> collected later (which slows down your program performance).
> You can have small Pojos, just try to avoid the call "new" in your functions:
>
> Instead of:
>
> class Mapper implements MapFunction<String,Pojo> {
> public Pojo map(String s) {
> Pojo p = new Pojo();
> p.f = s;
> }
> }
>
> do:
>
> class Mapper implements MapFunction<String,Pojo> {
> private Pojo p = new Pojo();
> public Pojo map(String s) {
> p.f = s;
> }
> }
>
> Then an object is only created once per Mapper and not per record.
>
> Hope this helps.
>
> Regards,
> Timo
>
>
>
> On 12.08.2015 11:53, Michael Huelfenhaus wrote:
>> Hello
>>
>> I have a question about the programming of user defined functions, is it
>> still like in old Stratosphere times the case that object creation should be
>> avoided al all cost? Because in some of the examples there are now Tuples
>> and other objects created before returning them.
>>
>> I gonna have an at least 6 step streaming plan and I am going to use Pojos.
>> Is it performance wise a big improvement to define one big pojo that can be
>> used by all the steps or better to have smaller ones to send less data but
>> create more objects.
>>
>> Thanks
>> Michael
>
