EJB 2.x EJB 3.0
Using another EJB: ejb-ref in XML descriptor Do JNDI lookup to get the home interface

Call home.create to obtain instance
ejb-ref no longer requires the home interface Change the home interface to the business interface

Remove home.create and directly invoke the methods on the EJB

Optionally annotate the EJB business interface property/field to obtain an instance
Resource access: Do JNDI lookup to obtain a resource Optionally annotate a resource property/field to obtain a resource

Table 1 Inject Simplification
EJB 3.0's principle of dependency injection simplifies the use of resources and EJB references. Annotation of the injection target or specification of the target in the ejb-jar.xml descriptor provides for the occurrence of resources or references. Compare the differences.