@Override
    public int hashCode() {
        int result = type != null ? type.hashCode() : 0;
        result = 31 * result + coordinatorEpoch;
        return result;
    }
This class represents the control record which is written to the log to indicate the completion
of a transaction. The record key specifies the {@link ControlRecordType control type} and the
value embeds information useful for write validation (for now, just the coordinator epoch).
clients/src/main/java/org/apache/kafka/common/record/EndTransactionMarker.java