--------------------------------------------------
BEAN ENVIRONMENT
--------------------------------------------------
1. The system administrator is responsible for adding, removing and configuring resource managers
in the EJB environment.

2. Can Environment entries can be shared with different enterprise beans ????????????????????????????

3. "<res-auth>Container</res-auth>"
Since the value of the res-auth element is Container, the deployer is responsible for configuring the
sign-in information of the resource manager by supplying the principle mapping information.
On the other hand, if the value of the res-auth element was Application the bean provider would be
responsible for performing a sign-on to the resource manager programmatically in the enterprise bean code.

4. Managed Resources :- The connections acquired through the resource manager connection factory references
are called managed resources.
Managed by J2EE container itself.
Administered Objects :- Managed by a separate server like a JMS provider or a JavaMail server.

5. Enterprise bean instances are NOT ALLOWED to modify the bean's environment at runtime.

6. Environment entry is INACCESSIBLE from other enterprise beans at runtime, and that other enterprise beans
may define env-entry elements with the same env-entry-name without causing a name conflict.

7. <env-entry> are NOT UNIQUE for instances of the same bean type. They share.

8. (String)initCtx.lookup("java:/comp/env/exchangeRate/japan");
(String)envCtx.lookup("exchangeRate/japan");