@Override public void write(Kryo kryo, Output output, Span span) {
      byte[] json = SpanBytesEncoder.JSON_V2.encode(span);
      output.writeInt(json.length);
      output.write(json);
    }
Example test for how to use Kryo and reuse our encoders
zipkin/src/test/java/zipkin2/codec/KryoTest.java