The EJB specification defines different roles in the development, assembly, and deployment of enterprise applications. The EJB architecture simplifies the development of complex business systems by dividing this process into six distinct roles, each with a specific task and objectives. These six roles address application development, infrastructure services, and deployment issues. Figure 1.5 illustrates the different roles involved in developing and deploying EJB components and applications.
In the next few sections, we will discuss these roles in more detail.