@Override
  public org.apache.hadoop.hbase.regionserver.MetricsUserSource createUser(String shortUserName) {
    return new org.apache.hadoop.hbase.regionserver.MetricsUserSourceImpl(shortUserName,
      getUserAggregate());
  }
Factory to create MetricsRegionServerSource when given a MetricsRegionServerWrapper
hbase-hadoop-compat/src/main/java/org/apache/hadoop/hbase/regionserver/MetricsRegionServerSourceFactoryImpl.java