@Override
    public boolean isFinished() {
        return currentSnapshotSplit == null
                || (!currentTaskRunning && !hasNextElement.get() && reachEnd.get());
    }
A snapshot reader that reads data from Table in split level, the split is assigned by primary key
range.
inlong-sort/sort-flink/sort-flink-v1.13/sort-connectors/mysql-cdc/src/main/java/org/apache/inlong/sort/cdc/mysql/debezium/reader/SnapshotSplitReader.java