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From Riccardo Ferrari <ferra...@gmail.com>
Subject Re: How to convert Row to JSON in Java?
Date Mon, 11 Sep 2017 07:39:23 GMT
Hi Ayan, yup that works very well however I believe Kant's other mail
"Queries with streaming sources must be executed with writeStream.start()"
is adding more context.
I think he is trying leverage on structured streaming and applying the rdd
conversion to a streaming dataset is breaking the streaming lineage.
Best,

On Mon, Sep 11, 2017 at 3:51 AM, ayan guha <guha.ayan@gmail.com> wrote:

> Sorry for side-line question, but for Python, isn't following the easiest:
>
> >>> import json
> >>>* df1 = df.rdd.map(lambda r: json.dumps(r.asDict()))*
> >>> df1.take(10)
> ['{"id": 1}', '{"id": 2}', '{"id": 3}', '{"id": 4}', '{"id": 5}']
>
>
>
>
> On Mon, Sep 11, 2017 at 4:22 AM, Riccardo Ferrari <ferrarir@gmail.com>
> wrote:
>
>> Hi Kant,
>>
>> You can check the getValuesMap
>> <https://spark.apache.org/docs/2.2.0/api/java/org/apache/spark/sql/Row.html#getValuesMap-scala.collection.Seq->.
>> I found this post <https://stackoverflow.com/a/41602178/8356352> useful,
>> it is in Scala but should be a good starting point.
>> An alternative approach is combine the 'struct' and 'to_json' functions
>> <https://spark.apache.org/docs/2.2.0/api/java/org/apache/spark/sql/functions.html>.
>> I have not tested this in Java but I am using it in Python.
>>
>> Best,
>>
>> On Sun, Sep 10, 2017 at 1:45 AM, kant kodali <kanth909@gmail.com> wrote:
>>
>>> toJSON on Row object.
>>>
>>> On Sat, Sep 9, 2017 at 4:18 PM, Felix Cheung <felixcheung_m@hotmail.com>
>>> wrote:
>>>
>>>> toJSON on Dataset/DataFrame?
>>>>
>>>> ------------------------------
>>>> *From:* kant kodali <kanth909@gmail.com>
>>>> *Sent:* Saturday, September 9, 2017 4:15:49 PM
>>>> *To:* user @spark
>>>> *Subject:* How to convert Row to JSON in Java?
>>>>
>>>> Hi All,
>>>>
>>>> How to convert Row to JSON in Java? It would be nice to have .toJson()
>>>> method in the Row class.
>>>>
>>>> Thanks,
>>>> kant
>>>>
>>>
>>>
>>
>
>
> --
> Best Regards,
> Ayan Guha
>

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