@Override
    public void getClient(String organizationId, String clientId, String clientVersion, IAsyncResultHandler<Client> handler) {
        String clientIdx = getClientIndex(organizationId, clientId, clientVersion);
        Client client = getClientInternal(clientIdx);
        handler.handle(AsyncResultImpl.create(client));
    }
@see io.apiman.gateway.engine.IRegistry#getClient(java.lang.String, io.apiman.gateway.engine.async.IAsyncResultHandler)
gateway/engine/core/src/main/java/io/apiman/gateway/engine/impl/InMemoryRegistry.java