APPTimerServiceBeanIT.java 文件源码

/**
 * Returns the first service instance entry found in the database.
 * 
 * @return A service instance.
 */
private ServiceInstance getServiceInstance() throws Exception {
    return runTX(new Callable<ServiceInstance>() {
        @Override
        public ServiceInstance call() throws Exception {
            Query query = em
                    .createQuery("SELECT si FROM ServiceInstance si");
            List<?> resultList = query.getResultList();
            if (resultList.isEmpty()) {
                return null;
            } else {
                return (ServiceInstance) resultList.get(0);
            }
        }
    });
}