@Override
    public void getClient(String organizationId, String clientId, String clientVersion,
            IAsyncResultHandler<Client> handler) {
        try {
            Client client = lookupClient(organizationId, clientId, clientVersion);
            handler.handle(AsyncResultImpl.create(client));
        } catch (ClientNotFoundException e) {
            handler.handle(AsyncResultImpl.create(e, Client.class));
        }
    }
@see io.apiman.gateway.engine.IRegistry#getApi(java.lang.String, java.lang.String, java.lang.String, io.apiman.gateway.engine.async.IAsyncResultHandler)
gateway/engine/es/src/main/java/io/apiman/gateway/engine/es/EsRegistry.java