archaius-core/src/main/java/com/netflix/config/ConfigurationManager.java
public static void loadPropertiesFromConfiguration(AbstractConfiguration config) {
        if (instance == null) {
            instance = getConfigInstance();
        }
        if (instance instanceof AggregatedConfiguration) {
            ((AggregatedConfiguration) instance).addConfiguration(config);
        } else {
            Properties props = ConfigurationUtils.getProperties(config);
            ConfigurationUtils.loadProperties(props, instance);
        }        
    }
public static void loadPropertiesFromConfiguration(AbstractConfiguration config) {
        if (instance == null) {
            instance = getConfigInstance();
        }
        if (instance instanceof AggregatedConfiguration) {
            ((AggregatedConfiguration) instance).addConfiguration(config);
        } else {
            Properties props = ConfigurationUtils.getProperties(config);
            ConfigurationUtils.loadProperties(props, instance);
        }        
    }
Load properties from the specified configuration into system wide configuration