avro-poc.avsc

{"namespace": "com.ricston.poc.avro",
 "type": "record",
 "name": "AvroPoc",
 "fields": [
      {"name": "id", "type": "int"},
      {"name": "name", "type": ["string","null"]},
      {"name": "surname", "type": ["string","null"]},
      {"name": "age", "type": ["int","null"]}
 ]
} 

AvroDeserializer.java

@Override
    public Object transformMessage(MuleMessage message, String outputEncoding)
            throws TransformerException {
        FileInputStream stream = (FileInputStream) message.getPayload();

        DatumReader<AvroPoc> dwDatumReader = new SpecificDatumReader<AvroPoc>(
                AvroPoc.class);

        List<AvroPoc> allUsers = new ArrayList<AvroPoc>();
        try {
            final DataFileStream<AvroPoc> dataFileReader = new DataFileStream<AvroPoc>(
                    stream, dwDatumReader);

            while (dataFileReader.hasNext()) {
                AvroPoc record = new AvroPoc();
                record = dataFileReader.next(record);
                allUsers.add(record);
            }
            stream.close();

            dataFileReader.close();
        } catch (Exception e) {
            throw new RuntimeException("Failed to serialize records",e);
        }

        message.setPayload(allUsers);

        return message;
    }

AvroSerializer.java

public Object transformMessage(MuleMessage message, String outputEncoding)
            throws TransformerException {

        List<AvroPoc> payload = (List<AvroPoc>) message.getPayload();
        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();

        Schema schema = ReflectData.get().getSchema(AvroPoc.class);
        ReflectDatumWriter<Object> reflectDatumWriter = new ReflectDatumWriter<Object>(
                schema);
        try {
            DataFileWriter<Object> writer = new DataFileWriter<Object>(
                    reflectDatumWriter).create(schema, outputStream);
            for (AvroPoc currentRecord : payload) {
                writer.append(currentRecord);
            }
            writer.close();
        } catch (IOException e) {
            throw new RuntimeException(e);
        }

        return outputStream.toByteArray();
    }

dataweave-csv-to-java.dwl

%dw 1.0
%output application/java
---
 payload map ((records) -> ({
     id: records.id as :number,
     name: records.name,
     surname: records.surname,
     age : records.age as :number
 }) as :object { class: "com.ricston.poc.avro.AvroPoc"})

dataweave-java-to-csv.dwl

%dw 1.0
%output application/csv
---
payload map ({
    id : $.id default 0,
    name : $.name default "",
    surname : $.surname default "",
    age : $.age default 0
})

fileoutbound.xml

<file:outbound-endpoint path="Avro-Processed"
            responseTimeout="10000" doc:name="File" outputPattern="avropoc-example-#[server.dateTime].avro"/>