@Override
      public Map<String, String> next() {
        return (iterator == null) ? null : iterator.next().toMap();
      }
Gets an iterator to use to access the records in the data file.
<p/>
Each item is a Map of column names to values.

@return an Iterator of records from the data file, each record is represented as a Map of
column name (String) to column value (String)
ambari-server/src/main/java/org/apache/ambari/server/serveraction/kerberos/AbstractKerberosDataFileReader.java