public HdfsSystemDescriptor withConsumerBlackList(String blackList) {
    this.consumerBlackList = Optional.ofNullable(StringUtils.stripToNull(blackList));
    return this;
  }
Black list used by directory partitioner to filter out unwanted files in a hdfs directory.
@param blackList black list for HDFS consumer inputs.
@return this system descriptor
samza-hdfs/src/main/java/org/apache/samza/system/hdfs/descriptors/HdfsSystemDescriptor.java