It would make sense to be able to check if something specific has changed in the configuration (e.g. the name) and also be able to get the previous name (e.g. for update of another service).

Example:

public class ConfigChangeListener implements ConfigurationListener {

@Override
public void onDelete(Configuration configuration) {
Context.getLogger().warn("delete " + configuration.getName());
}

@Override
public void onSave(Configuration configuration, Configuration previous) {
                if(previous == null) return; // configuration is new

if(!configuration.getName().equals(previous.getName())) {
                   // do something like external service data update
                }
}
}