Admin
 try {
            apiServerProxy = CtAdminApiPool.getInstance().getConnection();
        } catch (Exception ex) {
            Debug.traceException(this, ex);
            throw new AttributePluginException(ex);
        }

Runtime
        myRuntimeAPIPool = CtRuntimeApiPool.getInstance();
        if (myRuntimeAPIPool != null) {
            runtimeAPI = myRuntimeAPIPool.getRuntimeAPIConnection();

            if (runtimeAPI != null) {
                noRuntimeAPI = false;
            }
        }