code: public synchronized int cleanCache(float maxAge) {
  
          // calculate oldest possible date for the cache files
          long expireDate = System.currentTimeMillis() - (long)(maxAge * 60.0f * 60.0f * 1000.0f);
          File basedir = new File(m_rfsRepository);
          // perform the cache cleanup
          int count = 0;
          if (basedir.canRead() && basedir.isDirectory()) {
              File[] files = basedir.listFiles();
              if (files != null) {
                  for (int i = 0; i < files.length; i++) {
                      File f = files[i];
                      if (f.canWrite()) {
                          if (f.lastModified() < expireDate) {
                              try {
                                  f.delete();
                                  count++;
                              } catch (Exception e) {
                                  if (LOG.isWarnEnabled()) {
                                      LOG.warn(
                                          Messages.get().getBundle().key(
                                              Messages.LOG_EXCERPT_CACHE_DELETE_ERROR_1,
                                              f.getAbsolutePath()),
                                          e);
                                  }
                              }
                          }
                      }
                  }
              }
          }
          return count;
      }
docs: Removes all expired extraction result cache entries from the RFS cache.<p>
  
  @param maxAge the maximum age of the extraction result cache files in hours (or fractions of hours)
  
  @return the total number of deleted resources