Presentation Tier

The presentation tier of the application is implemented in Java using a platform independent smart client. The smart client provides the data management screens for the application. The use of smart client technology means that the users will have a feature-rich user interface that is responsive, functional, and comprehensive. The smart client will automatically manage software updates without the need for user intervention. The smart client will cache the application packages and optimize start up time.

The presentation tier of the application is implemented in Java using a platform independent smart client. The smart client provides the data management screens for the application. The use of smart client technology means that the users will have a feature-rich user interface that is responsive, functional, and comprehensive. The smart client will automatically manage software updates without the need for user intervention. The smart client will cache the application packages and optimize start up time.

Business Tier

The business tier of the application is implemented in Java using platform independent Java services and can be deployed on an application server. The business logic is contained within standard Java classes within this tier thus promoting the reusability of the business functionality. The business rules are encapsulated within Java components deployed on the application server. Validation of business rules defined on the business classes and will be verifiable at both the presentation tier and the business tier.
 
The business classes are persisted within the database using a data services layer consisting of business managers. The business managers automatically manage the object relational mapping between the business classes and the database. This includes the ability to create, retrieve, update, delete, associate, disassociate, and search for business data without the need to write SQL. The data services layer uses the standard Java JBDC API to manage the Oracle database. 
 
The application automatically manages the persistence of business objects using a relational database. It supports creating business objects, searching for business objects that match criteria, retrieving business objects, updating business objects, deleting business objects, associating business objects with one-another, and disassociating a business objects with one-another. The application automatically manages a pool of connections, support transactions and automatically perform object relational-mapping (ORM).
 
The smart client communicates with the business services using standard Java RMI; however, the business services can easily exposed as EJBs or Web Services. Use of web services will ensure that the correct business logic is always run before the data is entered or manipulated in the database. The business tier can be easily interfaced with standard messaging services using JMS.

Data Tier

The data tier of the application is implemented using a standard Oracle RDBMS deployed on a database server. The data model is normalized to 3rd normal form and referential integrity is enforced using primary key, and foreign keys, and the correct use of data types.  Business logic is not implemented in stored procedures or triggers; rather, it is contained with the service tier Java classes as specified above.