archaius-core/src/main/java/com/netflix/config/ConcurrentCompositeConfiguration.java
public void addConfiguration(AbstractConfiguration config, String name)
    {
        if (containerConfigurationChanged) {
            addConfigurationAtIndex(config, name, configList.size());
        } else {
            addConfigurationAtIndex(config, name, configList.indexOf(containerConfiguration));
        }
    }
public void addConfiguration(AbstractConfiguration config, String name)
    {
        if (containerConfigurationChanged) {
            addConfigurationAtIndex(config, name, configList.size());
        } else {
            addConfigurationAtIndex(config, name, configList.indexOf(containerConfiguration));
        }
    }
Adds a new child configuration to this configuration with an optional
name. The configuration will be added to the end of the list
if <em>container configuration</em> has been changed to new one or no longer at the end of
the list. Otherwise it will be added in front of the <em>container configuration</em>.

@param config the configuration to add (must not be <b>null</b>)
@param name the name of this configuration (can be <b>null</b>)