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From svante karlsson <s...@csi.se>
Subject Re: Deserialize Avro Object Without Schema
Date Wed, 25 Mar 2015 10:17:51 GMT
The schema is written inside an avro file. Thats why you don't need to
provide it. You really need the schema to decode avro data. Either by
providing a schema from somewhere and using a generic datum reader or by
generating a "hardcoded" decoder that knows the schema from compile time.

regards
svante

2015-03-25 11:10 GMT+01:00 Alexander Zenger <a.zenger@cetec.cc>:

> Hi,
>
> > -----Ursprüngliche Nachricht-----
> > Von: Rendy Bambang Junior [mailto:rendy.b.junior@gmail.com]
> > Gesendet: Mittwoch, 25. März 2015 10:08
> > An: user@avro.apache.org
> > Betreff: Deserialize Avro Object Without Schema
> >
> > It should be possible right? Since the schema itself is embedded in the
> data.
> >
> yes and it is working for me. Altough I'm reading data from a file, and I
> create a
> DataFileReader from the GenericDatumReader which then reads the
> deserialized data.
> On a quick look, I didn't find a FileReader for streams.
> Here is my example:
>
>    DatumReader<GenericRecord> datumReader = new
> GenericDatumReader<GenericRecord>();
>     DataFileReader<GenericRecord> dataFileReader = null;
>     try {
>       dataFileReader = new DataFileReader(DATA_FILE, datumReader);
>     } catch (IOException exp) {
>       System.out.println("Could not read file " + DATA_FILE.getName());
>       System.exit(1);
>     }
>
>     GenericRecord person = null;
>     try {
>       person = dataFileReader.next(person);
>     } catch (IOException exp) {
>       System.out.println("Could not read user from file " +
> DATA_FILE.getName());
>       System.exit(1);
>     }
>
>     System.out.println("Id:    " + person.get("id"));
>     System.out.println("Name:  " + person.get("name"));
>     System.out.println("Email: " + person.get("email"));
>
> --
> Regards
> Alexander Zenger
>
>
>

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