org.apache.avro.io.DatumWriter Java Examples

/**
 * Writes provided {@link GenericRecord} into the provided
 * {@link OutputStream} as JSON.
 */
public static void write(GenericRecord record, OutputStream out) {
    try {
        DatumWriter<GenericRecord> writer = new GenericDatumWriter<GenericRecord>(record.getSchema());
        JsonEncoder encoder = EncoderFactory.get().jsonEncoder(record.getSchema(), out);
        writer.write(record, encoder);
        encoder.flush();
    } catch (Exception e) {
        throw new IllegalStateException("Failed to read GenericRecord", e);
    }
}
 

@Test
public void testSingleAvroMessage() throws IOException {
    final TestRunner runner = TestRunners.newTestRunner(new ConvertAvroToJSON());
    final Schema schema = new Schema.Parser().parse(new File("src/test/resources/user.avsc"));

    final GenericRecord user1 = new GenericData.Record(schema);
    user1.put("name", "Alyssa");
    user1.put("favorite_number", 256);

    final DatumWriter<GenericRecord> datumWriter = new GenericDatumWriter<>(schema);
    final ByteArrayOutputStream out1 = AvroTestUtil.serializeAvroRecord(schema, datumWriter, user1);
    runner.enqueue(out1.toByteArray());

    runner.run();

    runner.assertAllFlowFilesTransferred(ConvertAvroToJSON.REL_SUCCESS, 1);
    final MockFlowFile out = runner.getFlowFilesForRelationship(ConvertAvroToJSON.REL_SUCCESS).get(0);
    out.assertContentEquals("{\"name\": \"Alyssa\", \"favorite_number\": 256, \"favorite_color\": null}");
}
 

AvroKeyValueWriter(Schema keySchema, Schema valueSchema,
		CodecFactory compressionCodec, OutputStream outputStream,
		int syncInterval) throws IOException {
	// Create the generic record schema for the key/value pair.
	mKeyValuePairSchema = AvroKeyValue
			.getSchema(keySchema, valueSchema);

	// Create an Avro container file and a writer to it.
	DatumWriter<GenericRecord> genericDatumWriter = new GenericDatumWriter<GenericRecord>(
			mKeyValuePairSchema);
	mAvroFileWriter = new DataFileWriter<GenericRecord>(
			genericDatumWriter);
	mAvroFileWriter.setCodec(compressionCodec);
	mAvroFileWriter.setSyncInterval(syncInterval);
	mAvroFileWriter.create(mKeyValuePairSchema, outputStream);

	// Create a reusable output record.
	mOutputRecord = new AvroKeyValue<Object, Object>(
			new GenericData.Record(mKeyValuePairSchema));
}
 

private ByteArrayOutputStream encodeAvroObject(org.apache.avro.Schema schema, int sourceId, Object datum) throws IOException {
    ByteArrayOutputStream out = new ByteArrayOutputStream();

    out.write(MAGIC_BYTE);
    out.write(ByteBuffer.allocate(ID_SIZE).putInt(sourceId).array());

    EncoderFactory encoderFactory = EncoderFactory.get();
    BinaryEncoder encoder = encoderFactory.directBinaryEncoder(out, null);
    Object
            value =
            datum instanceof NonRecordContainer ? ((NonRecordContainer) datum).getValue()
                    : datum;
    DatumWriter<Object> writer = new GenericDatumWriter<>(schema);
    writer.write(value, encoder);
    encoder.flush();

    return out;
}
 

AvroKeyValueWriter(Schema keySchema, Schema valueSchema,
		CodecFactory compressionCodec, OutputStream outputStream,
		int syncInterval) throws IOException {
	// Create the generic record schema for the key/value pair.
	mKeyValuePairSchema = AvroKeyValue
			.getSchema(keySchema, valueSchema);

	// Create an Avro container file and a writer to it.
	DatumWriter<GenericRecord> genericDatumWriter = new GenericDatumWriter<GenericRecord>(
			mKeyValuePairSchema);
	mAvroFileWriter = new DataFileWriter<GenericRecord>(
			genericDatumWriter);
	mAvroFileWriter.setCodec(compressionCodec);
	mAvroFileWriter.setSyncInterval(syncInterval);
	mAvroFileWriter.create(mKeyValuePairSchema, outputStream);

	// Create a reusable output record.
	mOutputRecord = new AvroKeyValue<Object, Object>(
			new GenericData.Record(mKeyValuePairSchema));
}
 

private Record writeAndRead(Schema writeSchema,
                            Schema readSchema,
                            Record record,
                            NameMapping nameMapping) throws IOException {

  File file = temp.newFile();
  // Write without file ids
  org.apache.avro.Schema writeAvroSchema = RemoveIds.removeIds(writeSchema);
  DatumWriter<Record> datumWriter = new GenericDatumWriter<>(writeAvroSchema);
  try (DataFileWriter<Record> dataFileWriter = new DataFileWriter<>(datumWriter)) {
    dataFileWriter.create(writeAvroSchema, file);
    dataFileWriter.append(record);
  }

  Iterable<GenericData.Record> records = Avro.read(Files.localInput(file))
      .project(readSchema)
      .withNameMapping(nameMapping)
      .build();

  return Iterables.getOnlyElement(records);
}
 

@Test
public void testExtractionWithCodec() throws IOException {
    final TestRunner runner = TestRunners.newTestRunner(new ExtractAvroMetadata());
    runner.setProperty(ExtractAvroMetadata.METADATA_KEYS, AVRO_CODEC_ATTR); // test dynamic attribute avro.codec

    final Schema schema = new Schema.Parser().parse(new File("src/test/resources/array.avsc"));

    final GenericData.Array<String> data = new GenericData.Array<>(schema, Arrays.asList("one", "two", "three"));
    final DatumWriter<GenericData.Array<String>> datumWriter = new GenericDatumWriter<>(schema);

    final ByteArrayOutputStream out = new ByteArrayOutputStream();
    final DataFileWriter<GenericData.Array<String>> dataFileWriter = new DataFileWriter<>(datumWriter);
    dataFileWriter.setCodec(CodecFactory.deflateCodec(1));
    dataFileWriter.create(schema, out);
    dataFileWriter.append(data);
    dataFileWriter.close();

    runner.enqueue(out.toByteArray());
    runner.run();

    runner.assertAllFlowFilesTransferred(ExtractAvroMetadata.REL_SUCCESS, 1);

    final MockFlowFile flowFile = runner.getFlowFilesForRelationship(ExtractAvroMetadata.REL_SUCCESS).get(0);
    flowFile.assertAttributeEquals("avro.codec", "deflate");
}
 

@Test
public void testSingleAvroMessage_noContainer() throws IOException {
    final TestRunner runner = TestRunners.newTestRunner(new ConvertAvroToJSON());
    runner.setProperty(ConvertAvroToJSON.CONTAINER_OPTIONS, ConvertAvroToJSON.CONTAINER_NONE);
    final Schema schema = new Schema.Parser().parse(new File("src/test/resources/user.avsc"));

    final GenericRecord user1 = new GenericData.Record(schema);
    user1.put("name", "Alyssa");
    user1.put("favorite_number", 256);

    final DatumWriter<GenericRecord> datumWriter = new GenericDatumWriter<>(schema);
    final ByteArrayOutputStream out1 = AvroTestUtil.serializeAvroRecord(schema, datumWriter, user1);
    runner.enqueue(out1.toByteArray());

    runner.run();

    runner.assertAllFlowFilesTransferred(ConvertAvroToJSON.REL_SUCCESS, 1);
    final MockFlowFile out = runner.getFlowFilesForRelationship(ConvertAvroToJSON.REL_SUCCESS).get(0);
    out.assertContentEquals("{\"name\": \"Alyssa\", \"favorite_number\": 256, \"favorite_color\": null}");
}
 

@Test
public void testSingleAvroMessage_wrapSingleMessage() throws IOException {
    final TestRunner runner = TestRunners.newTestRunner(new ConvertAvroToJSON());
    runner.setProperty(ConvertAvroToJSON.CONTAINER_OPTIONS, ConvertAvroToJSON.CONTAINER_ARRAY);
    runner.setProperty(ConvertAvroToJSON.WRAP_SINGLE_RECORD, Boolean.toString(true));
    final Schema schema = new Schema.Parser().parse(new File("src/test/resources/user.avsc"));

    final GenericRecord user1 = new GenericData.Record(schema);
    user1.put("name", "Alyssa");
    user1.put("favorite_number", 256);

    final DatumWriter<GenericRecord> datumWriter = new GenericDatumWriter<>(schema);
    final ByteArrayOutputStream out1 = AvroTestUtil.serializeAvroRecord(schema, datumWriter, user1);
    runner.enqueue(out1.toByteArray());

    runner.run();

    runner.assertAllFlowFilesTransferred(ConvertAvroToJSON.REL_SUCCESS, 1);
    final MockFlowFile out = runner.getFlowFilesForRelationship(ConvertAvroToJSON.REL_SUCCESS).get(0);
    out.assertContentEquals("[{\"name\": \"Alyssa\", \"favorite_number\": 256, \"favorite_color\": null}]");
}
 

@Test
public void testSingleAvroMessage_wrapSingleMessage_noContainer() throws IOException {
    final TestRunner runner = TestRunners.newTestRunner(new ConvertAvroToJSON());
    // Verify we do not wrap output for a single record if not configured to use a container
    runner.setProperty(ConvertAvroToJSON.CONTAINER_OPTIONS, ConvertAvroToJSON.CONTAINER_NONE);
    runner.setProperty(ConvertAvroToJSON.WRAP_SINGLE_RECORD, Boolean.toString(true));
    final Schema schema = new Schema.Parser().parse(new File("src/test/resources/user.avsc"));

    final GenericRecord user1 = new GenericData.Record(schema);
    user1.put("name", "Alyssa");
    user1.put("favorite_number", 256);

    final DatumWriter<GenericRecord> datumWriter = new GenericDatumWriter<>(schema);
    final ByteArrayOutputStream out1 = AvroTestUtil.serializeAvroRecord(schema, datumWriter, user1);
    runner.enqueue(out1.toByteArray());

    runner.run();

    runner.assertAllFlowFilesTransferred(ConvertAvroToJSON.REL_SUCCESS, 1);
    final MockFlowFile out = runner.getFlowFilesForRelationship(ConvertAvroToJSON.REL_SUCCESS).get(0);
    out.assertContentEquals("{\"name\": \"Alyssa\", \"favorite_number\": 256, \"favorite_color\": null}");
}
 

@Test
public void testMultipleAvroMessages() throws IOException {
    final TestRunner runner = TestRunners.newTestRunner(new ConvertAvroToJSON());
    final Schema schema = new Schema.Parser().parse(new File("src/test/resources/user.avsc"));

    runner.setProperty(ConvertAvroToJSON.CONTAINER_OPTIONS, ConvertAvroToJSON.CONTAINER_ARRAY);

    final GenericRecord user1 = new GenericData.Record(schema);
    user1.put("name", "Alyssa");
    user1.put("favorite_number", 256);

    final GenericRecord user2 = new GenericData.Record(schema);
    user2.put("name", "George");
    user2.put("favorite_number", 1024);
    user2.put("favorite_color", "red");

    final DatumWriter<GenericRecord> datumWriter = new GenericDatumWriter<>(schema);
    final ByteArrayOutputStream out1 = AvroTestUtil.serializeAvroRecord(schema, datumWriter, user1, user2);
    runner.enqueue(out1.toByteArray());

    runner.run();

    runner.assertAllFlowFilesTransferred(ConvertAvroToJSON.REL_SUCCESS, 1);
    final MockFlowFile out = runner.getFlowFilesForRelationship(ConvertAvroToJSON.REL_SUCCESS).get(0);
    out.assertContentEquals("[{\"name\": \"Alyssa\", \"favorite_number\": 256, \"favorite_color\": null},{\"name\": \"George\", \"favorite_number\": 1024, \"favorite_color\": \"red\"}]");
}
 

@Test
public void testMultipleAvroMessagesContainerNone() throws IOException {
    final TestRunner runner = TestRunners.newTestRunner(new ConvertAvroToJSON());
    final Schema schema = new Schema.Parser().parse(new File("src/test/resources/user.avsc"));

    runner.setProperty(ConvertAvroToJSON.CONTAINER_OPTIONS, ConvertAvroToJSON.CONTAINER_NONE);

    final GenericRecord user1 = new GenericData.Record(schema);
    user1.put("name", "Alyssa");
    user1.put("favorite_number", 256);

    final GenericRecord user2 = new GenericData.Record(schema);
    user2.put("name", "George");
    user2.put("favorite_number", 1024);
    user2.put("favorite_color", "red");

    final DatumWriter<GenericRecord> datumWriter = new GenericDatumWriter<>(schema);
    final ByteArrayOutputStream out1 = serializeAvroRecord(schema, datumWriter, user1, user2);
    runner.enqueue(out1.toByteArray());

    runner.run();

    runner.assertAllFlowFilesTransferred(ConvertAvroToJSON.REL_SUCCESS, 1);
    final MockFlowFile out = runner.getFlowFilesForRelationship(ConvertAvroToJSON.REL_SUCCESS).get(0);
    out.assertContentEquals("{\"name\": \"Alyssa\", \"favorite_number\": 256, \"favorite_color\": null}\n{\"name\": \"George\", \"favorite_number\": 1024, \"favorite_color\": \"red\"}");
}
 

@Test
public void testZeroRecords() throws IOException {
    final TestRunner runner = TestRunners.newTestRunner(new ConvertAvroToJSON());
    final Schema schema = new Schema.Parser().parse(new File("src/test/resources/user.avsc"));


    final DatumWriter<GenericRecord> datumWriter = new GenericDatumWriter<>(schema);
    final ByteArrayOutputStream out1 = serializeAvroRecord(schema, datumWriter);
    runner.enqueue(out1.toByteArray());

    runner.run();

    runner.assertAllFlowFilesTransferred(ConvertAvroToJSON.REL_SUCCESS, 1);
    final MockFlowFile out = runner.getFlowFilesForRelationship(ConvertAvroToJSON.REL_SUCCESS).get(0);
    out.assertContentEquals("{}");

}
 

@Override
public byte[] serialize(T t) {
    if (null == t) {
        return null;
    }

    // Writer to serialize Avro record into a byte array.
    DatumWriter<T> writer = new SpecificDatumWriter<>(t.getSchema());
    // Output stream to serialize records into byte array.
    ByteArrayOutputStream arrayOutputStream = new ByteArrayOutputStream();
    // Low-level class for serialization of Avro values.
    Encoder encoder = EncoderFactory.get().binaryEncoder(arrayOutputStream, null);
    arrayOutputStream.reset();
    try {
        writer.write(t, encoder);
        encoder.flush();
    } catch (IOException e) {
        throw new RuntimeException("Error while serializing the record to Avro", e);
    }

    return arrayOutputStream.toByteArray();
}
 

@Override
public void writeAvroFile(String pathToFile, String schemaName,
                          String codecName, IAvroSchema[] data)
        throws Exception {
    Path path = getDatapath(pathToFile);
    OutputStream outStream = fs.create(path, true, bufferSize,
            replicationSize, blockSize);
    Schema schema = new Schema.Parser().parse(new FileInputStream(
            schemaName));
    DatumWriter<GenericRecord> writer = new GenericDatumWriter<>(
            schema);
    DataFileWriter<GenericRecord> dataFileWriter = new DataFileWriter<>(
            writer);
    if (!StringUtils.isEmpty(codecName)) {
        dataFileWriter.setCodec(CodecFactory.fromString(codecName));
    }

    dataFileWriter.create(schema, outStream);

    for (IAvroSchema iAvroSchema : data) {
        GenericRecord datum = iAvroSchema.serialize();
        dataFileWriter.append(datum);
    }
    dataFileWriter.close();
}
 

@Override
protected Path createDataFile(ReaderFsTestConfig fsConfig, Object... args) throws IOException {
    File avroFile = File.createTempFile("test-", "." + getFileExtension());
    DatumWriter<GenericRecord> writer = new GenericDatumWriter<>(schema);
    try (DataFileWriter<GenericRecord> dataFileWriter = new DataFileWriter<>(writer)) {
        dataFileWriter.setFlushOnEveryBlock(true);
        dataFileWriter.setSyncInterval(32);
        dataFileWriter.create(schema, avroFile);

        IntStream.range(0, NUM_RECORDS).forEach(index -> {
            GenericRecord datum = new GenericData.Record(schema);
            datum.put(FIELD_INDEX, index);
            datum.put(FIELD_NAME, String.format("%d_name_%s", index, UUID.randomUUID()));
            datum.put(FIELD_SURNAME, String.format("%d_surname_%s", index, UUID.randomUUID()));
            try {
                fsConfig.offsetsByIndex().put(index, dataFileWriter.sync() - 16L);
                dataFileWriter.append(datum);
            } catch (IOException ioe) {
                throw new RuntimeException(ioe);
            }
        });
    }
    Path path = new Path(new Path(fsConfig.getFsUri()), avroFile.getName());
    fsConfig.getFs().moveFromLocalFile(new Path(avroFile.getAbsolutePath()), path);
    return path;
}
 

@SuppressWarnings("unchecked")
private static <D> DataFileWriter<D> newAvroWriter(
    Schema schema, OutputFile file, Function<Schema, DatumWriter<?>> createWriterFunc,
    CodecFactory codec, Map<String, String> metadata) throws IOException {
  DataFileWriter<D> writer = new DataFileWriter<>(
      (DatumWriter<D>) createWriterFunc.apply(schema));

  writer.setCodec(codec);

  for (Map.Entry<String, String> entry : metadata.entrySet()) {
    writer.setMeta(entry.getKey(), entry.getValue());
  }

  // TODO: support overwrite
  return writer.create(schema, file.create());
}
 

/**
 * tests Avro Serializer
 */
@Test
public void testSerializer() throws Exception {
    Context context = new Context();
    String schemaFile = getClass().getResource("/schema.avsc").getFile();
    context.put(ES_AVRO_SCHEMA_FILE, schemaFile);
    avroSerializer.configure(context);
    Schema schema = new Schema.Parser().parse(new File(schemaFile));
    GenericRecord user = generateGenericRecord(schema);
    DatumWriter<GenericRecord> datumWriter = new GenericDatumWriter<>(schema);
    ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
    Encoder encoder = new EncoderFactory().binaryEncoder(outputStream, null);
    datumWriter.write(user, encoder);
    encoder.flush();
    Event event = EventBuilder.withBody(outputStream.toByteArray());
    XContentBuilder expected = generateContentBuilder();
    XContentBuilder actual = avroSerializer.serialize(event);
    JsonParser parser = new JsonParser();
    assertEquals(parser.parse(Strings.toString(expected)), parser.parse(Strings.toString(actual)));
}
 

public byte[] serializeMessage(S clazz, String path) {

        byte[] result = null;
        try {

            File file = new File(path);

            Schema schema = new Schema.Parser().parse(file);

            ByteArrayOutputStream out = new ByteArrayOutputStream();
            BinaryEncoder encoder = EncoderFactory.get().binaryEncoder(out, null);
            DatumWriter<S> dataFileWriter = new SpecificDatumWriter<S>(schema);
            dataFileWriter.write(clazz, encoder);
            encoder.flush();
            result=out.toByteArray();
            out.close();
        }catch (Exception ex){
            ex.printStackTrace();
        }
        return result;
    }
 

@Override
public DatumWriter<T> createDatumWriter(T data, Schema schema) {
    if (data instanceof SpecificRecord) {
        return new SpecificDatumWriter<>(schema);
    } else {
        return new GenericDatumWriter<>(schema);
    }
}
 

@Override
protected void serializeData(Schema schema, U data, OutputStream out) throws IOException {
    BinaryEncoder encoder = encoderFactory.directBinaryEncoder(out, null);

    // I guess this can happen if generics are lost with reflection ...
    if (data instanceof NonRecordContainer) {
        //noinspection unchecked
        data = (U) NonRecordContainer.class.cast(data).getValue();
    }

    DatumWriter<U> writer = avroDatumProvider.createDatumWriter(data, schema);
    writer.write(data, encoder);
    encoder.flush();
}
 

@Override
public byte[] serialize(String topic, Record record) {
  try (ByteArrayOutputStream baos = new ByteArrayOutputStream()) {
    baos.write(DataDeserializer.MAGIC_BYTE);
    baos.write(Ints.toByteArray(VERSION));
    DatumWriter<Object> writer = new GenericDatumWriter<>(SCHEMA);
    BinaryEncoder encoder = EncoderFactory.get().directBinaryEncoder(baos, null);
    writer.write(record, encoder);
    encoder.flush();
    return baos.toByteArray();
  } catch (IOException unreachable) {
    throw new RuntimeException(unreachable);
  }
}
 

private byte[] toAvroBinary(Schema schema, Object value, int version) {
  try (ByteArrayOutputStream baos = new ByteArrayOutputStream()) {
    baos.write(0x0);
    baos.write(Ints.toByteArray(version));
    DatumWriter<Object> writer = new GenericDatumWriter<>(schema);
    Encoder encoder = EncoderFactory.get().directBinaryEncoder(baos, null);
    writer.write(value, encoder);
    encoder.flush();
    return baos.toByteArray();
  } catch (IOException e) {
    throw new RuntimeException(e);
  }
}
 

private byte[] toAvroBinary(Schema schema, Object value, int version) {
  try (ByteArrayOutputStream baos = new ByteArrayOutputStream()) {
    baos.write(0x0);
    baos.write(Ints.toByteArray(version));
    DatumWriter<Object> writer = new GenericDatumWriter<>(schema);
    Encoder encoder = EncoderFactory.get().directBinaryEncoder(baos, null);
    writer.write(value, encoder);
    encoder.flush();
    return baos.toByteArray();
  } catch (IOException e) {
    throw new RuntimeException(e);
  }
}
 

private static byte[] encode(Record record) throws IOException {
  try (ByteArrayOutputStream buffer = new ByteArrayOutputStream()) {
    Encoder encoder = EncoderFactory.get().directBinaryEncoder(buffer, null);
    DatumWriter<Object> writer = new GenericDatumWriter<>(record.getSchema());
    buffer.write(0x00);
    buffer.write(Ints.toByteArray(1));
    writer.write(record, encoder);
    encoder.flush();
    return buffer.toByteArray();
  }
}
 

private AvroFactory(
	GenericData avroData,
	Schema schema,
	DatumReader<T> reader,
	DatumWriter<T> writer) {

	this.avroData = checkNotNull(avroData);
	this.schema = checkNotNull(schema);
	this.writer = checkNotNull(writer);
	this.reader = checkNotNull(reader);
}
 

@Override
public void open(int taskNumber, int numTasks) throws IOException {
	super.open(taskNumber, numTasks);

	DatumWriter<E> datumWriter;
	Schema schema;
	if (org.apache.avro.specific.SpecificRecordBase.class.isAssignableFrom(avroValueType)) {
		datumWriter = new SpecificDatumWriter<E>(avroValueType);
		try {
			schema = ((org.apache.avro.specific.SpecificRecordBase) avroValueType.newInstance()).getSchema();
		} catch (InstantiationException | IllegalAccessException e) {
			throw new RuntimeException(e.getMessage());
		}
	} else if (org.apache.avro.generic.GenericRecord.class.isAssignableFrom(avroValueType)) {
		if (userDefinedSchema == null) {
			throw new IllegalStateException("Schema must be set when using Generic Record");
		}
		datumWriter = new GenericDatumWriter<E>(userDefinedSchema);
		schema = userDefinedSchema;
	} else {
		datumWriter = new ReflectDatumWriter<E>(avroValueType);
		schema = ReflectData.get().getSchema(avroValueType);
	}
	dataFileWriter = new DataFileWriter<E>(datumWriter);
	if (codec != null) {
		dataFileWriter.setCodec(codec.getCodecFactory());
	}
	if (userDefinedSchema == null) {
		dataFileWriter.create(schema, stream);
	} else {
		dataFileWriter.create(userDefinedSchema, stream);
	}
}
 

private AvroFactory(
	GenericData avroData,
	Schema schema,
	DatumReader<T> reader,
	DatumWriter<T> writer) {

	this.avroData = checkNotNull(avroData);
	this.schema = checkNotNull(schema);
	this.writer = checkNotNull(writer);
	this.reader = checkNotNull(reader);
}
 

@Override
public void open(int taskNumber, int numTasks) throws IOException {
	super.open(taskNumber, numTasks);

	DatumWriter<E> datumWriter;
	Schema schema;
	if (org.apache.avro.specific.SpecificRecordBase.class.isAssignableFrom(avroValueType)) {
		datumWriter = new SpecificDatumWriter<E>(avroValueType);
		try {
			schema = ((org.apache.avro.specific.SpecificRecordBase) avroValueType.newInstance()).getSchema();
		} catch (InstantiationException | IllegalAccessException e) {
			throw new RuntimeException(e.getMessage());
		}
	} else if (org.apache.avro.generic.GenericRecord.class.isAssignableFrom(avroValueType)) {
		if (userDefinedSchema == null) {
			throw new IllegalStateException("Schema must be set when using Generic Record");
		}
		datumWriter = new GenericDatumWriter<E>(userDefinedSchema);
		schema = userDefinedSchema;
	} else {
		datumWriter = new ReflectDatumWriter<E>(avroValueType);
		schema = ReflectData.get().getSchema(avroValueType);
	}
	dataFileWriter = new DataFileWriter<E>(datumWriter);
	if (codec != null) {
		dataFileWriter.setCodec(codec.getCodecFactory());
	}
	if (userDefinedSchema == null) {
		dataFileWriter.create(schema, stream);
	} else {
		dataFileWriter.create(userDefinedSchema, stream);
	}
}
 

AvroFileAppender(Schema schema, OutputFile file,
                 Function<Schema, DatumWriter<?>> createWriterFunc,
                 CodecFactory codec, Map<String, String> metadata,
                 boolean overwrite) throws IOException {
  this.stream = overwrite ? file.createOrOverwrite() : file.create();
  this.writer = newAvroWriter(schema, stream, createWriterFunc, codec, metadata);
}