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From Pawan Manishka Gunarathna <pawan.manis...@gmail.com>
Subject Re: [Dev] Dependencies issue related to implementing InputFormat Interface
Date Wed, 18 Jan 2017 11:14:46 GMT
Hi,

Thanks Fabian and Chesnay for providing those information.

Pawan

On Wed, Jan 18, 2017 at 2:11 PM, Chesnay Schepler <chesnay@apache.org>
wrote:

> Hello,
>
> The dependencies are fine.
>
> The short answer is i would recommend you to read op on java generics.
>
> The long answer is that OT and T are just placeholders for types that are
> supposed to be replaced.
>
> You can either provide the type in your implementation:
> (in this example, the ReadFromFile inputformat returns the data as strings)
>
>    public class ReadFromFile implements InputFormat<String, InputSplit>{
>    }
>
> or add a generic parameter to your inputformat:
>
>    public class ReadFromFile<OT, T extends InputSplit > implements
>    InputFormat<OT, T>{
>    }
>
>    In this case, the type would be specified when instantiating the
>    Inputformat:
>
>        new ReadFromFile<String, InputSplit>(...);
>
> Note that you can also mix this; i.e define the InputSplit type (T) in
> your implemenetation, but leave
> OT to the user.
>
> Regards,
> Chesnay
>
>
>
> On 18.01.2017 04:52, Pawan Manishka Gunarathna wrote:
>
>> Hi,
>> Yeah I also wrote in the way you have written......
>>
>> public class ReadFromFile implements InputFormat<OT,T extends InputSplit>{
>> }
>>
>> Is that a problem with that declaration or dependencies ?
>>
>> Thanks,
>> Pawan
>>
>> On Tue, Jan 17, 2017 at 7:56 PM, Chesnay Schepler <chesnay@apache.org>
>> wrote:
>>
>> Hello,
>>>
>>> Did you write something like this?
>>>
>>>     public class MyInputFormat implements InputFormat<OT, T extends
>>>     InputSplit> {
>>>          ....
>>>     }
>>>
>>> Regards,
>>> Chesnay
>>>
>>> On 17.01.2017 04:18, Pawan Manishka Gunarathna wrote:
>>>
>>> Hi,
>>>>
>>>> I'm currently working on Flink InputFormat Interface implementation. I'm
>>>> writing a java program to read data from a file using InputputFormat
>>>> Interface. I used maven project and I have added following dependencies
>>>> to
>>>> the pom.xml.
>>>>
>>>> <dependencies>
>>>>       <dependency>
>>>>           <groupId>org.apache.flink</groupId>
>>>>           <artifactId>flink-core</artifactId>
>>>>           <version>1.1.4</version>
>>>>       </dependency>
>>>>
>>>>       <dependency>
>>>>           <groupId>org.apache.flink</groupId>
>>>>           <artifactId>flink-clients_2.11</artifactId>
>>>>           <version>1.1.4</version>
>>>>       </dependency>
>>>>
>>>>       <dependency>
>>>>           <groupId>org.apache.flink</groupId>
>>>>           <artifactId>flink-java</artifactId>
>>>>           <version>1.1.4</version>
>>>>       </dependency>
>>>>
>>>> </dependencies>
>>>>
>>>>
>>>> I have a java class that implements InputFormat. It works with
>>>> *InputFormat.
>>>> *But it didn't allow to used *InputFormat<OT, T extends InputSplit>.
>>>> *That
>>>> OT field didn't recognized.
>>>>
>>>> I need a any kind of help to solve this problem.
>>>>
>>>> Thanks,
>>>> Pawan
>>>>
>>>>
>>>>
>>
>


-- 

*Pawan Gunaratne*
*Mob: +94 770373556*

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