@Override
        public String toString() {
            return String.format(
                "LocalRecordBatch(leaderEpoch=%s, appendTimestamp=%s, records=%s)",
                leaderEpoch,
                appendTimestamp,
                records
            );
        }
The LocalLogManager is a test implementation that relies on the contents of memory.
metadata/src/test/java/org/apache/kafka/metalog/LocalLogManager.java