The second stage reading summary of UML elephant

In the second stage, I read the basic and advanced articles.

The basic concept of UML is re-organized and summarized, extended and discussed, and the application of these concepts in the object-oriented approach to UML is deduced. The Advanced chapter is an example of how to implement a project from beginning to end using UML.

First, from the real world to the business model. In the real world, no matter what industry, no matter what business, its essence is composed of people, things, things and rules. People are the center of everything, people want to do things, things will use some things and produce some things, at the same time do things need to follow certain rules. The human drive system, the thing manifests the process, the material records the result, the rule is the control. While the use cases in UML can express the rules of human things, "participants" represent people, "use cases" represent things, "business scenarios" and "use case scenarios" embody rules through UML views, while "business object models" represent the objects used in the middle. This way the real world maps to the business object model. Through this step, a method of mapping the real world to the object world is found.

Second, from the business object model to the conceptual model. The previous business object model, which describes the real world in UML, is far from real computer software. When the business model is described by an analytic class, we have actually adopted the object's perspective. The actual business process represented by use cases is replaced by concepts such as "boundary", "control", "Entity" and "package" and "component". And these concepts can be understood by the computer, is an abstract object, the real world is very diverse business, all with these fixed elements to express, that is, the real world has been abstracted into a few fixed concepts. It can be said that from the business model to the conceptual model we need a way to describe the real world from the object world.

Finally, from the conceptual model to the design model, the objects "boundary", "control," and "entity" are understandable to the computer, but not real object instances, not executable code. It should be converted to java,c#,c++ code to execute. Where the "boundary" class can be mapped to the corresponding "interface", "control" can be mapped to "control class", "entity" can be mapped to the corresponding "entity class", so that the conceptual model from the map to the design model.

Through the above three steps, the use of object-oriented analysis and design method to the real world through the derivation, and eventually converted into a software system can be run. And from the design of the class to the conceptual model, and then to the object model, step-by-step verification of the original real world. Software system is no longer the head to think out, nor copy the previous project changed to change out, but through a certain method step by step to come out.

The example in the advanced article inspired me very well, as a novice to learn the soft work, see a real project is how to develop the sincerity is not easy, at the same time I also found on the Internet many predecessors wrote the book, they are working for several years of people, introduced their work in the field is how to develop projects, for me very useful.

The second stage reading summary of UML elephant