The University of Anytown School of Business Computing

Problem Situation Student Retention Too many students enrol on a course then withdraw in their first year Need a software system to help solve the problem – An improved school intranet

Start with a mind map (or rich picture)

Develop a Process Map 1.Admissions 2.Pastoral Care 3.Timetabling 4.Module Delivery 5.Peer Tutoring 6.Assessment 7.Attendance Monitoring 8.Research

Definition of a Pastoral Services System A system under the control of an in-school counselling team – giving appropriate referrals to external agencies to students presenting personal problems to members of the counselling team.

Root Definition for Peer-Tutoring A system owned by the school that provides study skills support to students using volunteers from the student body with the quality of their support activities monitored by academic staff

Activity Diagram for Peer-Tutoring

Things that could be added to the activity diagram Is it enough to advertise? – Should some students be made to attend? Should we pay peer tutors? – Money? – Credits? How should the effectiveness of the system be measured?

Attendance Monitoring

Related Use Cases Let’s consider this one

Create Class List

The information displayed here might be brought together through collaboration between objects

Class Diagram showing relationships between these objects

We can do two things with this class diagram Implement it in an OOPL Translate it into an entity model then implement the entity model as a relational database CASE tools can help with both of these

Three Very Simple Use Cases Create New Supplier Delete Supplier Update Supplier Details Let’s consider some coding issues!

One “Entity” Class

Three Control Classes Create New Supplier Delete Supplier Update Supplier Details

One Boundary Class for all Three Use Cases

One Boundary Class

One Class to Talk to the Database

Sequence Diagram for Create New Supplier Supplier Form Control Class “Create Supplier” Entity Class “Supplier” DB Connection DBSupplier

Overview of the System Architecture

Project Window for the entire application

More Sophisticated Use Cases Perhaps we could ask the Customer object to: – Project future sales to this customer. This would involve analysing past sales to identify trends. Implies the need for a “Customer Sales History” class not currently included in the model. – Collect overdue payments. This would involve generating standard letters to be sent to the customer. Implies collaboration with a “Payment” class (associated with Order or Invoice?) not currently included in the model.

Select Add Class Module from the Project menu Building the Module Maintenance Application in VB

Use the Class Builder

Click the Button to add a new class

Give the Class a Decent Name

Click the Button to Add an Attribute

Give the Attribute a Name and Data Type

Select this Button to Add an Operation

Name the Operation

When we Update the Project the necessary code is generated to implement the class

Using a collection to implement a 1:M relationship We might want to implement a Module class that knows the many pathways on which the module is taught One of the attributes of this module class will be a collection of pathways!

Back to the Class Builder Assume we’ve created the classes clsModule and clsPathway We now need to create a class that can manage a collection of pathway objects Create this collection by clicking this button

Use the Collection Builder To name the collection And indicate what it is a collection of..

Sequence Diagram A VB form allows us to select a Module (from a drop down list) and then see a list of the pathways the module is taught on This involves asking a Module object to ask each of the pathways in its MyPathways collection to display their title. In UML we document this type of collaboration in a sequence diagram

We’ll see how Rational Rose can help Generate a VB class module from a class diagram Generate an entity model from the class diagram Generate a database from the entity model

Create a VB6 Model

Add a Class

Associate the Model with a VB project

Generated Program Link to the Rose model

Once this connection has been made… We can.. – Update the VB project from our model – Update our model from the VB project Round-trip engineering

Now for the database..

First tell Rose about the target database

Set up a schema for the target database

Now generate the entity model

Generate the Database from the Schema

Example of Generated SQL