public String getConfigurationValue(String key, String defaultValue) {
    return this.configuration.getProperty(dbMonitorPrefix + key, defaultValue);
  }
Method to get Configuration value given key. An extra prefix is added internally.
@param key
@param defaultValue
@return Value corresponding to key = dbMonitorPrefix + key
ambari-server/src/main/java/org/apache/ambari/server/metrics/system/impl/DatabaseMetricsSource.java