Flashcards
3 - domain modelling to requiremnts
Cards in this deck (16)
- 1What are the important properties that a representation of business rules should have?* Business rules that apply to the whole business shuld be seperate from project specific models
*They should be easy to verify (possibly automated)
*Should be in a readable language that is easy to verify. - 2business ruleA constraint on how the business is run; that is, a constraint on the business processes.
- 3Explain the activites verification and validation and how business rules are important.* Verification is the set of activities that ensure that a solution is being correctly developed, in this case, taking into account the buisness rules.(can be automatic)
* Validation ensures what is being built satisfies the business. ie the rules implemented dare the ones that the busines wants. - 4business processDefinition of what gets done in the business: by whom, in what order, needing what and with what consequences.
- 5use caseA description, of a piece of functionality that a system performs to yield an observable result of some value to an actor. (See also task.)
- 6Name two aspects of software development where use case modelling can help.eliciting requirements and representing requirements
- 7What is the purpose of a system boundary? Is it always necessary to draw one in a use case diagram?The purpose of a system boundary is to identify a single system, distinguishing between the internal and external components. Typically, the external components are the actors and the internal components are the use cases. UML says that the system boundary is optional.
- 8What is the relationship between a use case and a scenario?For each use case there is a set of possible scenarios. A scenario is an instance of a use case. A scenario describes a sequence of interactions between the system and some actors.
- 9What is meant by a main success scenario?The main success scenario shows the steps normally followed to achieve the stated goal of the use case. But there can be other scenarios for the same use case, each one having different outcomes depending upon circumstances.
- 10How do use cases help with: requirements capture?Use cases help with requirements capture through the identification of actors and tasks in the system. For each actor, the set of use cases establishes what that actor requires from the software system. The association between an actor and a use case is about communication.
- 11How do use cases help with: the elicitation of detailed software requirementsDetailed software requirements can be associated with each step in a use case scenario. There may be more than one requirement for each step.
- 12How do use cases help with: system validation (checking that the system actually supports the functionality required by the users)?One way to validate a system is to use the walk-through technique, checking the functionality related to each use case in turn. The walk-through technique can also be used to elicit system tests where each use case is required to deal with a number of scenarios – a process known as verification. For each software requirement generated from a step of a scenario, the fit criterion helps to devise the test.
- 13What is a stereotype in UML?A stereotype is a way of attaching extra classifications to a model adding to its basic language. Stereotypes can be user defined – this is a way of extending UML.
- 14What is the meaning of the «include» stereotype?The «include» stereotype indicates a situation where a use case is reused. In Figure 13, the diagram illustrates the check reservation use case, which is used by two other use cases. The purpose is to demonstrate commonality between tasks so that reuse can be achieved. The additional use case is included unconditionally in the original (base) use case.
- 15What is the meaning of the «extend» stereotype?The «extend» stereotype indicates a conditional extension to the original use case, known as alternative behaviour. This is used to illustrate a case where there are two or more significantly different scenarios, so that the main case and the additional subsidiary cases are clearly differentiated. The main purpose of this classification is to separate out a special case. You should add a condition to each extension – with either a note or an extension point – to specify when the variant behaviour will be included
- 16What are the main differences between a use case and a user story?A use case describes a business process or a self-contained task within a process. It is as complete as possible, lasts as a document, is agreed (by customers and developers) and is used to generate requirements.
A user story is small enough to be implemented in a single iteration, represents an instance from a user perspective, is not complete, does not last and instead is used as a reminder for a conversation.
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- software engineering (3 - From domain modelling to requirements) Flashcards on 3 - domain modelling to requiremnts, created by Claire Lemon on 01/11/2016.
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- Claire Lemon
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