A multi tier CD catalog management application
This site recurrent example
Purpose of the example
Our recurrent example consist in building a CD catalog management application. It will be use by many tutorials on this site such as the Struts framework tutorial, the HSQLDB tutorial, an others... We will use a multi tier model so that each tutorial can focus on its concerns only. For example, a database tutorial will focus on the data access and not on the user interface.
UML modelisation
A CD catalog is a set of CD with wich a user can interact : he can add a CD to the catalog, get all the CDs of the desired artist, remove a CD from the catalog, ... Here, we will limit the interaction to 7 possible actions :
Use case diagram
- addToCatalog
- Allow the user to add a CD to the catalog.
- getById
- Allow the user to retrieve a CD from the catalog according to it's id.
- updateInCatalog
- Allow the user to update a CD in the catalog.
- removeFromCatalog
- Allow the user to remove a CD from the catalog.
- listByName
- Allow the user to retrieve a list of CDs that match the given name.
- listByArtist
- Allow the user to retrieve a list of CDs that match the given artist name.
- searchByCriteria
- Allow the user to retrieve a list of CDs according to different parameters.
Java architecture
Our java example skeleton is divided into 4 packages :
- cd.catalog.dao
- The data access object is used to perform CRUD and more complex operations on data. It handles mapping objects and it's implementation depends on the underlying data storage engine : database (MySQL, HSQLDB, Oracle, ...), file system, memory, ...
- cd.catalog.exception
- This package contains Exception classes that can be raised by Services and Data access object implementations.
- cd.catalog.mapping
- This package contains low level beans used to map data from the data storage engine.
- cd.catalog.service
- The service classes perform the business logic and control the application functionalities. A service implementation depends on the way a service is accessed and on the desired service restriction : a delete functionality will only be available for a local administration tool and not for an exposed web service.
The Service interface, Dao interface and CD mapping object are defined bellow :
Java class definition
Download the java library : CD catalog librairy
