public QuotaFilter setNamespaceFilter(final String regex) {
    this.namespaceRegex = regex;
    hasFilters |= StringUtils.isNotEmpty(regex);
    return this;
  }
Set the namespace filter regex
@param regex the namespace filter
@return the quota filter object
hbase-client/src/main/java/org/apache/hadoop/hbase/quotas/QuotaFilter.java