Multitier Application Scenario
The multitier application scenario consists of EJB and web components. The applications
business logic can be hosted in both containers. The use of EJB has advantages by making
business logic available outside of web applications.
Multitier applications are not strictly preferable for testing purposes. But the
monitoring and querying of EJBs is easier than doing this job with web components. Hereby
the entity beans are easier to test than session beans because the latter have either no
identity (being stateless) or are non reentrant (statefull) during a test.
Still without a clear demarcation of responsibilities between web and EJB components a
multitier design will not result in easier tests.
Multitier applications are not the silver bullet to tackle quality assurance problems