ejbcertificate.com - package

[Kris Reid]

Can some one please clarify this question



dentify correct programming restrictions that a Bean provider must follow to ensure that the enterprise bean is portable and can be deployed in any compliant EJB 2.0 Container. [Check all correct answers]

1. The enterprise bean cannot define read and write to static fields.

2. The enterprise bean cannot make use of the Java Swing API.

3. The enterprise bean cannot make use of interfaces to define business methods.

4. The enterprise bean cannot make use of the Sun JavaMail API.

5. The enterprise bean must not attempt to define a class in a package.




Answer 1, 2 and 5 are correct.

Answer 1 is correct. This rule is required to ensure consistent runtime semantics because while some EJB Containers may use a single JVM to execute all enterprise bean's instances, others may distribute the instances across multiple JVMs.

Answer 2 is correct. Most servers do not allow direct interaction between an application program and a keyboard/display attached to the server system.

Answer 5 is correct. This function is reserved for the EJB Container. Allowing the enterprise bean to perform this function would create a security hole.






I understand 1 and 2. But number 5 doesn't seem to make sense. Is it refering to the bean class not being in a package?

e.g.
package headfirst;

public class AdviceBean implements SessionBean {

[Keerthi P]

It means some of the defineXXX() methods from java.lang.ClassLoader should not be used. Refer API here

[Kris Reid]

That makes sense that you can't define a class using ClassLoader
but (forgive me if I'm wrong) ClassLoader.defineClass() doesn't have anything to do with a package.