@Override
    public SplitEnumerator<MySqlSplit, PendingSplitsState> restoreEnumerator(
            SplitEnumeratorContext<MySqlSplit> enumContext, PendingSplitsState checkpoint) {
        MySqlSourceConfig sourceConfig = configFactory.createConfig(0);

        final MySqlSplitAssigner splitAssigner;
        if (checkpoint instanceof HybridPendingSplitsState) {
            splitAssigner =
                    new MySqlHybridSplitAssigner(
                            sourceConfig,
                            enumContext.currentParallelism(),
                            (HybridPendingSplitsState) checkpoint);
        } else if (checkpoint instanceof BinlogPendingSplitsState) {
            splitAssigner =
                    new MySqlBinlogSplitAssigner(
                            sourceConfig, (BinlogPendingSplitsState) checkpoint);
        } else {
            throw new UnsupportedOperationException(
                    "Unsupported restored PendingSplitsState: " + checkpoint);
        }
        return new MySqlSourceEnumerator(enumContext, sourceConfig, splitAssigner);
    }
Get a MySqlParallelSourceBuilder to build a {@link MySqlSource}.

@return a MySql parallel source builder.
inlong-sort/sort-flink/sort-flink-v1.15/sort-connectors/mysql-cdc/src/main/java/org/apache/inlong/sort/mysql/source/MySqlSource.java