@Override
    public int hashCode() {
      return new HashCodeBuilder(17, 37)
        .append(expectedComponentCount)
        .append(matchPattern)
        .append(realmPattern)
        .toHashCode();
    }
Get the match component count. This is the number of components that are evaluated
when attempting to match a principal to the rule.
ambari-server/src/main/java/org/apache/ambari/server/controller/AuthToLocalBuilder.java