@Override
    public String toString() {
        return "LagInfo {" +
            " currentOffsetPosition=" + currentOffsetPosition +
            ", endOffsetPosition=" + endOffsetPosition +
            ", offsetLag=" + offsetLag +
            '}';
    }
Get the measured lag between current and end offset positions, for this store partition replica

@return lag as measured by message offsets
streams/src/main/java/org/apache/kafka/streams/LagInfo.java