JAM

JAM is an open source stack that includes Java, Apache web server, its servlet container, and MySQL database. It offers an architecture that is best suited for an enterprise distributed environment.

Architecture Overview

Client Tier

The client tier interacts with the user and displays information from the system to the user. J2EE supports different types of clients, including web HTML client, Java applets and applications.

Web Tier

The Web tier generates the presentation logic and accepts user responses from the presentation clients, which are typically HTML clients, Java applets and other Web clients. Based on the received client request, the presentation tier generates the appropriate responses to the client request that it receives. In the J2EE platform, servlet and JSP in a Web container implement this tier.

Business Tier

This tier handles the core business logic of the application. The business tier provides the necessary interfaces to the underlying business service components. The business components are typically implemented as EJB components with support from EJB container that facilitates the component life cycle and manages persistence, transactions and the resource allocation.

Database Tier

This tier is responsible for the enterprise information systems, including database systems and enterprise resources.