Object-Oriented Design

Exam3 Review

Last updated: Fall '03 (4/15/2003)

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Closed book, no notes, no calculators, etc.
Few multiple choice and fill in the blank questions; some open questions.
Notice that almost all questions that call for a definition (formal) or description (informal) require an illustration (example) of the concept. So, as you study each question below, consider the definition and also illustrate with an example.

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Scope

All materials to date. The main focus will be on materials presented since the last exam.

Be prepared to give examples based on program code. This does not mean that you will necessarily write code; however, it means you must know, and describe, code as used in .NET.

Data Tier

• What are some common problems that arise from poor design?
• How can intermediate objects help overcome common design problems?
• How can an object model be made persistent?
• Define the term, Impedance Mismatch.
• For what purpose is an Intermediary used, in the context of the data tier?
• Define and use (with UML) the following two persistence patterns: Domain-Proxy-Broker, and Domain-Broker
• What patterns are used in the WEO data tier? How does it work?

Transactions

• What is a transaction?
• What is rollback?
• What is a commit?
• When are transactions useful?
• Do you suppose there is an overhead in using transactions?
• What does it mean to programmatically define a transaction? Give an example.
• What does it mean to declarative define a transaction? Give an example.

Security

• What are some general goals of security?
• What are Access Control Lists?
• What is a Role-base Access Control?
• How does the SOS system do: authentication and authorization?

Business Tier

• What is N-Tier Design?
• Illustrate a logical architecture for .NET showing tiers from GUI rendering to data. Define some physical .NET elements that fulfill the logical roles shown in your illustration.
• What is a component?
• What are benefits of using component-based development?

Integrative Reasoning

Consider the design of a on-line store and answer the following questions:

• Define a (simple) logical network architecture diagram, illustrating the tiers the servers that run them.
• Define a physical network architecture diagram that shows how each tier will be implanted; for example, using .NET components or newly designed and programmed components. Include references to software frameworks, such as WEO, if they are to be used.
• Describe how object persistence will be managed. If WEO or ObjectSpacs is to be used, describe its function and how it works.
• Describe how transactions will be managed.
• Describe how security will be managed.
• Using UML, define any components that will be necessary (e.g., Order, Order-line, Product).