public Builder flinkConf(ReadableConfig flinkConf) {
      this.flinkConf = flinkConf;
      return this;
    }
An util class create mixed-format source data stream.
amoro-format-mixed/amoro-mixed-flink/amoro-mixed-flink-common/src/main/java/org/apache/amoro/flink/table/FlinkSource.java