private String getWriterClassName() {
    // class name which is recognized by hbase-1.x to avoid ProtobufLogReader throwing error:
    // IOException: Got unknown writer class: AsyncProtobufLogWriter
    if (encryptor == null) {
      return "ProtobufLogWriter";
    } else {
      return "SecureProtobufLogWriter";
    }
  }
Base class for Protobuf log writer.
hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/wal/AbstractProtobufLogWriter.java