UML software engineering organization
Beijing Dragon Fruit Software Engineering Technology Center
How to determine the needs of CRC model: ♀ Wang Zheng bleak ♂ Quoted 51CMM.COM
CRC (Class-Responsibility-Collaborator) card modeling is a simple and valid object-oriented analysis technology. In an OO (object-oriented) development project, including users, system analysts, and developers often apply CRC card modeling during modeling and design, so that the entire development team is universally understood.
It consists of three parts:
Class (Class)
2. Responsibility
3. Collaborator
A class represents many similar objects. The object is a matter of concern in system modeling. They can be a person, place, things, or any concept that is important to the system. Class names are typically column at the top of the CRC card.
Responsibilities are anything you need to know or do. These responsibilities are knowledge of the class, or the knowledge required to execute.
Collaboration refers to other classes that have been grouped or assisted in executive activities. In a specific case, a (or many) step is set together with the specified class. Collaborative classes are arranged in the right side of the CRC card.
The CRC model is a collection of CRC cards representing all or part of an application domain or problem domain. The CRC model is the most common user, where the white paper address is used to collect and define user needs of object-oriented applications. A CRC model example of a shipping / inventory control system is shown, and the displayed CRC card will be placed on a desk or work desk. Note the placement of the card: The card collaborate is close to each other, and the unrelated card cannot be placed nearby.
Let's talk about how to create a CRC model? There are six steps: 1, the CRC model group is joined (the model group includes related customer sector people, designers, recorders, system analysts, etc.). 2, arrange the model room. 3. Perform collective free discussion content according to the system objective of this CRC model, if the system is developed? What supports do business services need this system? What information does it need when working? ...... In short, try to perform the goals achieved by the system requirements, including the requirements of resources, conditions, activities, and personnel. 4, explain CRC model technology (after completion of the collective discussion, the designer will describe the CRC model process. It usually takes ten to fifteen minutes, including the creation of several CRC card exemptions, paragraph references). 5. Repeat the CRC model step. 6. Execution Example Scenario Test User Scenario Test is a task process mode, where users will actively participate in ensuring demand is accurate. Basic ideas are a group of business sector experts (that is, customer party), designer, system analysts step by step through a series of use cases to accurately reflect the user's needs accurately. In fact, the CRC model is a communication method, how the customer party and the developer have established a system demand that can describe the accuracy, both parties to achieve consensus. CRC modeling because users are actively involved in the definition of the model, and their satisfaction with work will increase, and create this CRC model with developers. Through this series of model cards, both parties have reached a consensus . Of course there is a certain disadvantage, the CRC model is just a part of the user's demand definition of object-oriented applications. You should also take into account use cases, prototype, and formal demand documents. Whether to use CRC modeling,
