You can re-use the GenericRecord object you used before and then just
re-serialize. If you've been given the byte array, then you can
deserialize to a GenericRecord using something similar to this:
reader = new GenericDatumReader<GenericRecord>(schema);
Decoder decoder = DecoderFactory.get().binaryDecoder(bytes, null);
GenericRecord record = reader.read(null, decoder);
record.put("user_id", 123456L);
-Joey
On Mon, Jan 12, 2015 at 5:21 PM, Check Peck <comptechge...@gmail.com> wrote:
> Yes that's what I am looking for. Question is - How do I update the
> GenericRecord, I want to update user_id field with some new random long
> number.?
>
> Can you provide an example how can I update GenericRecord and then serialize
> it to a new Byte Array?
>
> On Mon, Jan 12, 2015 at 4:34 PM, Joey Echeverria <j...@cloudera.com> wrote:
>>
>> I'm not sure I understand the question. You can certainly deserialize
>> the byte array back into a GenericRecord. You can then update that
>> GenericRecord and serialize that to a new byte array.
>>
>> Is that what you're looking for?
>>
>> -Joey
>>
>> On Mon, Jan 12, 2015 at 3:42 PM, Check Peck <comptechge...@gmail.com>
>> wrote:
>> > I have an Avro Schema which is like this -
>> >
>> > {
>> > "type":"record",
>> > "name":"new_user",
>> > "namespace":"com.hello",
>> > "fields":[
>> > {
>> > "name":"user_id",
>> > "type":[
>> > "long",
>> > "null"
>> > ]
>> > },
>> > {
>> > "name":"segment",
>> > "type":[
>> > "string",
>> > "null"
>> > ]
>> > }
>> > ]
>> > }
>> >
>> > I am using my above Avro Schema like this to serialize the data and
>> > which
>> > gives me a Byte Array and works fine -
>> >
>> > public static void main(String[] args) throws IOException {
>> > Schema schema = new Parser()
>> > .parse("{ \"type\":\"record\", \"name\":\"new_user\",
>> > \"namespace\":\"com.hello\", \"fields\":[ { \"name\":\"user_id\",
>> > \"type\":[
>> > \"long\", \"null\" ] }, { \"name\":\"segment\", \"type\":[ \"string\",
>> > \"null\" ] } ] }");
>> >
>> > byte[] originalAvrodata = getAvroBinaryData(schema);
>> >
>> > // how to get newAvroData byte array in which user_id
>> > // is change to some other random long number?
>> > }
>> >
>> > private static byte[] getAvroBinaryData(Schema schema) throws
>> > IOException {
>> > GenericRecord record = new GenericData.Record(schema);
>> > record.put("user_id", 123456L);
>> > record.put("segment", "hello");
>> >
>> > GenericDatumWriter<GenericRecord> writer = new
>> > GenericDatumWriter<GenericRecord>(schema);
>> > ByteArrayOutputStream os = new ByteArrayOutputStream();
>> >
>> > Encoder e = EncoderFactory.get().binaryEncoder(os, null);
>> >
>> > writer.write(record, e);
>> > e.flush();
>> > byte[] byteData = os.toByteArray();
>> > return byteData;
>> > }
>> >
>> >
>> >
>> > I need to decode the `originalAvrodata` byte array and then change the
>> > `user_id` field value to some other `long` number and then construct a
>> > `newAvroData` byte array using the same schema which should have
>> > `user_id`
>> > field value to some random `long` number. Is this possible to do by any
>> > chance using Avro?
>>
>>
>>
>> --
>> Joey Echeverria
>
>
--
Joey Echeverria
