How do you inject a JPA EntityManager(Factory) using JSF on Tomcat?

Is it possible to configure JPA to inject EntityManager or
EntityManagerFactory on Tomcat?

I'm reading
<http://openjpa.apache.org/docs/latest/manual/>
and
<http://java.sun.com/javaee/5/docs/tutorial/doc/bnbrm.html#bnbrp>

I'm not using Spring or like framework. I have Sun's JSF libs, along with
MyFaces and Tomahawk, plus Apache OpenJPA installed in the project.

I aim to use persistence annotations to declare a class's EntityManagerFactory
member, like this:

public class Foo
{
     @PersistenceUnit( unitName="myPersist" )
     private EntityManagerFactory emf;
....
}

or likewise for an EntityManager member:

public class Fiz
{
     @PersistenceContext( unitName="myPersist" )
     private EntityManager em;
....
}

NetBeans thinks it knows all about JPA, so it already helpfully created a data
source definition for my database (e.g., "jdbc/myDs") and a persistence.xml to
map it (e.g., to "myPersist").

My questions are:

- Is there a way to achieve this resource injection given a JSP / JSF
framework on Tomcat, without adding Spring or the like?

- Is Spring a solution to this? Are there others like it?

- Generally how would one configure a web application to use JPA by resource
injection?

I'm working lately on getting this to work within Glassfish, which explicitly
claims to support injecting JPA this way.

--
Lew