In attempting to identify objects focus on stored data and processing coming from the problem space. Nouns in descriptions are agood examples.

After identifitying objects you need to narrow down to those you will use in the code. Reasons for inclusion of objects

• needed history (does systme need to remember states)
• Needed services
• 1 attribute
• common attributes or services (- classification structure)
• essential requirements (part of specification)

Reasons for exclusion of objects: things that you don't need.

• unneeded services
• unneeded history
• only 1 instance of object
• derived (mathematically) result

source psfile jl@crush.caltech.edu index OOA_steps