EJB can be of the following types according to the EJB3 specification:

• Session bean:

• • Stateful session bean
  • Stateless session bean
  • Singleton session bean

• Message-driven bean

We will discuss message-driven bean (MDB) in detail in a Chapter 10, Asynchronous Programming with JMS, when we learn about asynchronous processing of requests in the JEE application. In this chapter, we will focus on session beans.