![The Object-Relationship Model contd..
Identifying a relationship:
• Rumbaugh and his colleagues [RUM91] suggest that relationships can be derived by
examining the stative verbs or verb phrases in the statement of scope or use-cases
for the system.
• Using a grammatical parse, the analyst isolates verbs that
indicate physical location or placement (next to, part of, contained in),
communications (transmits to, acquires from),
ownership (incorporated by, is composed of), and
Satisfaction of a condition (manages, coordinates, controls).
• These provide an indication of a relationship.](https://image.slidesharecdn.com/objectrelationshipmodel-140610123608-phpapp01/85/Object-relationship-model-of-software-engineering-a-subtopic-of-object-oriented-analysis-5-320.jpg)
Object relationship model of software engineering,a subtopic of object oriented analysis.
- 1. The Object- Relationship Model By Balasara kshiar Mca 4th sem St anthonys College
- 2. The Object-Relationship Model • The first step in establishing relationships is to understand the responsibilities for each class in the CRC model. • The CRC model index card contains a list of responsibilities. • The next step is to define those collaborator classes that help in achieving each responsibility. • This establishes the “connection” between classes.
- 3. The Object-Relationship Model contd.. Control panel Determine sensor status Set sensor status ………. …….. Sensor Sensor Recognize smoke Recognize break-in …………. …………. Sensor event
- 4. The Object-Relationship Model contd.. • The most common type of relationship is binary—a connection exists between two classes. • a binary relationship has a specific direction that is defined based on which class plays the role of the client and which acts as a server.
- 5. The Object-Relationship Model contd.. Identifying a relationship: • Rumbaugh and his colleagues [RUM91] suggest that relationships can be derived by examining the stative verbs or verb phrases in the statement of scope or use-cases for the system. • Using a grammatical parse, the analyst isolates verbs that indicate physical location or placement (next to, part of, contained in), communications (transmits to, acquires from), ownership (incorporated by, is composed of), and Satisfaction of a condition (manages, coordinates, controls). • These provide an indication of a relationship.
- 6. The Object-Relationship Model contd.. • The object relationship model can be derived in three steps: 1.Using the CRC index cards, a network of collaborator objects can be drawn 2.Reviewing the CRC model index card, responsibilities and collaborators are evaluated and each unlabeled connected line is named. 3.Once the named relationships have been established, each end is evaluated to determine cardinality Four options exist: 0 to1 1 to 1 0 to many 1 to many.
- 7. The Object-Relationship Model contd.. Fig: Relationship between objects