Scala Avro encoding and decoding to bytes without using additional libraries (From Confluent or Twitter)

AvroCodec.scala

import java.io.ByteArrayOutputStream

import org.apache.avro.Schema
import org.apache.avro.io.{BinaryDecoder, BinaryEncoder, DatumReader, DatumWriter, DecoderFactory, EncoderFactory}
import org.apache.avro.reflect.{ReflectDatumReader, ReflectDatumWriter}
import org.apache.avro.specific.SpecificRecordBase

class AvroCodec[A <: SpecificRecordBase](schema: Schema) {

  val decoderFactory: DecoderFactory = DecoderFactory.get()
  val avroReader: DatumReader[A] = new ReflectDatumReader[A](schema)

  val encoderFactory: EncoderFactory = EncoderFactory.get()
  val avroWriter: DatumWriter[A] = new ReflectDatumWriter[A](schema)

  def decode(bytes: Array[Byte], reuseDecoder: Option[BinaryDecoder] = Option.empty): A = {
    val decoder = decoderFactory.binaryDecoder(bytes, reuseDecoder.orNull)
    avroReader.read(null.asInstanceOf[A], decoder)  // scalastyle:ignore null
  }

  def encode(bytes: A, reuseEncoder: Option[BinaryEncoder] = Option.empty): Array[Byte] = {
    val stream = new ByteArrayOutputStream
    val binaryEncoder = encoderFactory.binaryEncoder(stream, reuseEncoder.orNull)
    avroWriter.write(bytes, binaryEncoder)
    binaryEncoder.flush()
    stream.toByteArray
  }
}

I had trouble tracking down example code for directly converting to or from Avro when using Kafka. Many of the examples use either Confluent's library, which I believe depends upon using schema-registry already, or Twitter's Bijection library. I'm not saying to avoid those libraries, but I wanted raw encoding and decoding to prove some stuff out.