protected StoresImpl<K,E> constructStores() throws IOException
{
final SCONFIG sconfig = serviceConfig();
StoreBackendBuilder<?> b = sconfig.instantiateBackendBuilder();
StoreBackendConfig backendConfig = sconfig._storeBackendConfigOverride;
if (backendConfig == null) { // no overrides, use databinding
Class<? extends StoreBackendConfig> cfgType = b.getConfigClass();
if (sconfig.storeBackendConfig == null) {
throw new IllegalStateException("Missing 'config.storeBackendConfig");
}