Developing Business Logic with EJB 3.0 
EJB components are an essential part of Java EE applications. In the SAP NetWeaver Developer Studio, you create EJB 3.0 components (as of the Java EE 5 specification) in EJB 3.0 Projects.
More information: EJB Overview
Procedure
Create an EJB 3.0 Project.
More information: Creating EJB 3.0 Projects in the Developer Studio
Use the corresponding wizards to create enterprise beans and helper classes.
More information:
Implement the business logic.
You can use the following features:
(Optional) Use dependency injection to use external resources.
More information: Using Dependency Injection
(Optional) Configure the EJB References and Environment Entries using the SAP NetWeaver Administrator.
More information: Editing EJB Environment
(Optional) Change the default transaction configuration in which the EJB runs.
More information: Specifying Transaction Attributes
(Optional) Specify the security roles that are allowed to invoke the EJB methods using the security-related metadata annotations.
More information: Specifying Security
(Optional) Program and configure the business interceptor method or life cycle callback interceptor method.
More information: Using Interceptors and Life Cycle Callbacks
(Optional) Use Java Persistence API.
More information: Using Java Persistence API (JPA)
(Optional) To operate with the database, you can use predefined templates that generate stateless session bean facade, which implements the create, read, update, delete (CRUD) facade.
More information:
(Optional) Expose your Enterprise JavaBeans as Web service endpoints.
More information: Using Enterprise JavaBeans as Web Service Endpoints
(Optional) Edit the EJB deployment descriptors to configure the application.
More information: Editing the ejb-j2ee-engine.xml
(Optional) Access Enterprise JavaBeans from non-Java EE applications.
More information: Accessing Enterprise JavaBeans from Remote Clients
(Optional) If you want to provide methods to allow callbacks to be scheduled for time-based events, use the EJB Timer service.
More information: Using Timers
(Optional) You can use business logic that is part of SAP NetWeaver 2004 AS Java or SAP NetWeaver 7.0 AS Java.
More information: Connecting to Enterprise Beans on SAP NetWeaver 2004 AS Java and SAP NetWeaver 7.0 AS Java
If you have not done so initially, add the EJB 3.0 Project to an Enterprise Application.
More information: Creating Enterprise Application Projects