private void initCleanerChain(String confKey) {
    this.cleanersChain = new ArrayList<>();
    String[] cleaners = conf.getStrings(confKey);
    if (cleaners != null) {
      for (String className : cleaners) {
        className = className.trim();
        if (className.isEmpty()) {
          continue;
        }
        T logCleaner = newFileCleaner(className, conf);
        if (logCleaner != null) {
          LOG.info("Initialize cleaner={}", className);
          this.cleanersChain.add(logCleaner);
        }
      }
    }
  }
Instantiate and initialize all the file cleaners set in the configuration
@param confKey key to get the file cleaner classes from the configuration
hbase-server/src/main/java/org/apache/hadoop/hbase/master/cleaner/CleanerChore.java