@SuppressWarnings("unchecked")
    public synchronized void offset(Map<String, ?> partition, Map<String, ?> offset) {
        data.put((Map<String, Object>) partition, (Map<String, Object>) offset);
    }
Set an offset for a partition using Connect data values
@param partition the partition to store an offset for
@param offset the offset
connect/runtime/src/main/java/org/apache/kafka/connect/storage/OffsetStorageWriter.java