HelloBased on Avro schema I generated a class (Data) to work with the class
appropriate to the schema
After it I encode the data and send in to other application "A" using kafka
Data data; // <- The object was initialized before . Here it is only the
declaration "for example"
EncoderFactory encoderFactory = EncoderFactory.get();
ByteArrayOutputStream out = new ByteArrayOutputStream();
BinaryEncoder encoder = encoderFactory.directBinaryEncoder(out, null);
DatumWriter<Tloog> writer;
writer = new SpecificDatumWriter<Data>(Data.class);
writer.write(data, encoder);
byte[] avroByteMessage = out.toByteArray();
On the other side (in the application "A") I deserilize the the data by
implementing Deserializer
class DataDeserializer implements Deserializer<Data> {
private String encoding = "UTF8";
@Override
public void configure(Map<String, ?> configs, boolean isKey) {
// nothing to do
}
@Override
public Tloog deserialize(String topic, byte[] data) {
try {
if (data == null)
{
return null;
}
else
{
DatumReader<Tloog> reader = new
SpecificDatumReader<Data>(Data.class);
DecoderFactory decoderFactory = DecoderFactory.get();
BinaryDecoder decoder =
decoderFactory.binaryDecoder(data, null);
Data decoded = reader.read(null, decoder);
return decoded;
}
} catch (Exception e) {
throw new SerializationException("Error when deserializing byte[]
to string due to unsupported encoding " + encoding);
}
}
The problem is that this approach requires the use of
SpecificDatumReader<Data>, I.e.the Data class should be integrated with the
application code...This could be problematic - schema could change and
therefore Data class should be re-generated and integrated once more
2 questions:
- Should I use GenericDatumReader in the application? How to do that
correctly. (I can save the schema simply in the application)
- Is there a simple way to work with SpecificDatumReader if Data changes?
How could it be integrated with out much trouble?
Thanks
