Precautions when using Singleton Session Beans

Processing of threads waiting for acquisition of Write lock is not interrupted by stopping the application.
If a circular dependency is specified in the @DependsOn annotation, an error occurs in the deploy processing when the application starts.
With Application Server, you cannot specify the @DependsOn annotation for a Singleton Session Bean for different EJB-JAR files.
In the lifecycle callback method (PostConstruct or PreDestroy) of a Singleton Session Bean, specification of the transaction attribute of the @TransactionAttribute annotation is invalid.