The main contents of the previous period include:
First, standard modeling language UML overview
Second, the standard modeling language UML static modeling mechanism
Third, standard modeling language UML dynamic modeling mechanism
Fourth, standard modeling language UML support environment
V. Application examples of standard modeling language UML
1. UML modeling process high-level view
2. UML actual modeling process
(1) demand
(2) analysis
(Connecting) (3) The task of designing design phases is to extend and refine the model of the analysis phase by comprehensively considering all technical limits to expand and refine the model. The purpose of the design is to indicate a work program that is easy to convert to code is the refinement of analysis, that is, further refine the class (including its operations and attributes) extracted in the analysis phase, and increasing new categories to handle, such as databases. Problems in technical fields such as user interface, communication, equipment. The design phase can be divided into two parts: structural design is high-level design, its mission is to define the package (subsystem), including the dependence and main communication mechanism between the package. We hope to get as simple and clear structures, depending on the dependence as small as possible, and reduce the bidirectional dependencies as possible. The second part is a detailed design, refining the content of the package, so that the programmer gets a sufficiently clear description of all classes. Simultaneous use of dynamic models in UML, the behavior between these classes is described in a particular case. • Structure Design A good design is a basis for system-expandable and changeable. The package is actually a collection of some classes. The class diagram includes help users separate application logic (domain classes) from technical logic, thereby reducing the dependence between them. This is the principle of high polymerization and low coupling between the software structure design emphasized. In commercial MIS, there is a package (or subsystem): user interface package: User interface class allows users to access system data and add new data. In the business object, the user interface packs with the business object package, calls the operation of the business object, implement the search and insertion of the data. Business object packages: including specific domains from the analysis phase. In the design phase, these classes are designed in detail to complete their operations to support access to the database. Therefore, all commercial object classes must inherit the class in the database package. Database Pack: Provide services for class in the commercial object package for permanent storage. Package: Contains services to use for other packages. The intrinsic relationship between them is shown in Figure 1. · Detailed design detailed design is to describe the new technical class and expand and refine the business object class "Sketch" by creating new class diagrams, state diagrams and dynamics. These images have been used in the analysis phase, but in the detailed design phase, they are more detailed in the system from the technical level. If the use example of the analysis phase is used to verify that they are processed in the design phase, and the sequence diagram is used to display how each used case in the system is technically implemented, and so on. Database Package: The implementation of MIS must have a permanent storage object that is, the database is supported, so the database layer must be added to provide this service. At present, there are many commercial databases on the market, and some are real object-oriented databases such as engineering databases, and some are traditional databases. Since we only discuss design methods, do not involve specific environments, therefore, you can abstract a permanent storage class to implement common operations for databases, such as storage, update, deletion, query, etc. Permanent class is similar to the base class in the MFC. Commercial object package: The commercial object package in the design phase is the domain class of the analysis phase, which needs to be refinered from the achievement angle, including how to achieve the association and behavior between them. All of these object classes must be inherited from the permanent class of the database package. The operation of the class described in the analysis phase may be decomposed into several operations or change the name in the design model. Because the analysis is to construct the framework of each class, the design is a detailed description of the system, so the operations of all classes in the design model must define symbols and return values. 2 is a state diagram (partial) in the design phase, also detailed in the design phase, and more detailed display state (Figure 3). Using the status map can reveal the details of the variation of a single object throughout the system, which is helpful for understanding and implementing key classes. In addition, other images can be used to refine the models established from different sides on different sides on the implementation layer. User interface package: User interface package "top" in other packages. In the system, it provides information and support for users. Since all interactions with the user are implemented through the user interface, the dynamic model of the UML is ideal for a description of the GUI package. Figure 4 shows the dynamic model of the new commodity usage with the sequence diagram description system. Another figure representation is a cooperation diagram (Figure 5). Establishing a user interface is a special event in the design phase. In commercial MIS, the user interface can be divided into functions (main function windows in the system, such as procurement, inventory, sales, statistical analysis, etc.), information (display system information window, etc.) and other three parts. Currently Due to the rapid development of visualization techniques, the user interface is relatively simple. In general, the user interface of the application system consists of a main window with a menu strip and a corresponding graphic. (4) Implementing the construction or implementation of the class is Procedures for programming. You can choose some object-oriented object programming language (such as Java) as a software environment for implementing the system. Java is easy to implement mappings from logical views to code parts, because class to Java code files are one-one mapping relationship Figure 6 is a component diagram of a design model, a simple mapping of the logical view to the part view. The package in the logical view is also mapped to the corresponding part view.
In the implementation phase, the description of the following graphs can be selected to assist programming: • Specifications for classes: Specifications for each class displays the necessary properties and operations in detail. · Class diagram: The relationship between the static structure and classes of the class. · Status Figure: Display the object of the object, the transfer you want, and the operation of triggering these transfers. · A dynamic diagram (sequential diagram, cooperation diagram, active diagram) containing a class (sequential diagram, cooperation): displaying the implementation or other object of a method of the class or other objects using this class. · Use examples and specifications: display system requirements and results. Design model defects may also be found during encoding. At this time, the developer needs to modify the design model. To modify the design model, you must maintain the consistency of design models and coding for future maintenance. (5) After testing and configuring the system encoding, you need to test the system, which usually includes: unit testing, integrated testing, system testing, and acceptance testing. Test the specifications of the class diagrams and classes in unit tests, test separate classes or group classes; in integrated testing, use component diagrams and cooperation maps, testing the cooperation of each component; in system testing, Use an example example to verify that the system is described in the demand described in the example. The configuration of the system is the actual delivery system, including documents and composition models, and more. For business MIS, it is a typical client / server system. The physical structure of the system can be displayed with the configuration diagram, as shown in Figure 7. From the surface, the configuration diagram can display the relationship between the system devices and the corresponding relationship between the node follows the executable software unit. However, once an object or executable component inside a node is too large (more than 5), it is difficult to clearly describe this relationship. (6) Summary The UML modeling process of the commercial MIS system lifted herein can be described in Figure 8. Among them, we must first grasp how to use the use case technology to correctly describe the system requirements. The class diagram in the UML describes the static relationship between the system, and the object map helps to understand complex classes. During the system development, class diagrams can be applied to analysis, design, and implementation. The package of classes helps to perform system structure design. Commercial MIS package is divided into user interface packages, commercial object packages, database packages, and the relationship between them is the former reliance. The dynamic model of the UML includes state diagrams, sequential diagrams, cooperation graphs, and activity diagrams. In commercial MIS, the sequence diagram is very useful to describe the interaction of business objects, which is one of the most important support for commercial MIS analysis, design and implementation.
In summary, the nine views provided by UML are analyzed from systematic analysis from different application hies and different angles, and design itself until achieving support. Establish different models in different stages, the purpose of modeling is different.
UML provides strong support for user modeling and provides a lot of freedom. User can fully select the various types provided by UML according to the characteristics of its own development system, in accordance with the characteristics of its own development system. Fig.
In the UML application, choose the right tool is also important. For simple applications, Visio, Msword and other tools can support the generation of various desired graphics. But they are static graphics, they cannot support the modeling and optimization of the system. The North Air Technology Institute is developing and developing the UML integrated support system, which is designed and developed to fill the blanks of my country's software industry.
We believe that future software development paradigms will have the following three features: First, software development automation will become higher and higher; second, hidden errors in the software developed will be less and less; third, in new With the support of the software engineering environment, it will be able to develop an adaptive software system. Standard Modeling Language UML and its integrated support environment will be paved towards this new path (full text).
