Future Education Chapter 5 Topic Notes_UML and Database Application System
2. The sequence diagram is mainly used to describe the message sending and receiving sequence between system objects. It has two coordinate axes: the vertical represents the continuous process of time, the horizontal represents the object, each object is represented by a rectangular box, and the vertical dashed line represents the execution of the object in the sequence. The first message of the sequence diagram is generally at the top of the lifeline of the first object on the left, and other messages are inserted into the sequence diagram in chronological order. The line of the subsequent messages should be drawn lower than the line of the previous messages. To express the time relationship between them.
3. The component diagram provides a physical view of the system. The purpose of the component diagram in UML graphics is to display the dependence of the software in the system on other software components (such as library functions). It can be displayed at a very high level, so that only coarse-grained components can be displayed, or in component packages. Hierarchical display.
4. The relationship between the class and the class:
generalization (hollow triangle solid line connection, arrow pointing to the parent class), generalization, also known as generalization
realization (hollow triangle dotted line connection, arrow pointing to the interface),
aggregation (hollow diamond solid line connection, Rhombus points to the whole),
combination (solid diamond-shaped solid line connection, diamonds point to the whole),
association (solid line with ordinary arrows, pointing to the owner),
dependence (dotted line with arrows, pointing to the user).
The representation of the class refers to the inheritance of the subclass to the parent class; the interface is similar to the subclass inheritance, and the difference is mainly in multiple inheritance; the aggregation relationship mainly represents a weak ownership relationship, such as A object can contain B object, but The B object is not a part of the A object; while composition is a kind of strong possession, which embodies the strict partial and overall relationship.
5. Use case diagram is a model diagram of system functions that external users (participants) can observe. It shows use cases and roles in the system and their relationships. It is mainly used to model the functions of systems, subsystems or classes. The use case diagram model consists of three parts: use case, role and system.
7. The time chart is suitable for when the state transition is closely related to time, while emphasizing the important role of the time factor in the state transition process.
9. The structure diagram refers to a graph that takes the calling relationship of the module as a clue, and uses a top-down connection to indicate the calling relationship and indicates the direction and content of parameter transfer, which reflects the hierarchical structure of the module from a macro perspective. The structure diagram includes use case diagrams, class diagrams, component diagrams, object diagrams, and deployment diagrams.
10. The RecordSet object is used to manipulate data from the provider. When using ADO, almost all data can be manipulated through the RecordSet object. All RecordSet objects are constructed using records (rows) and fields (columns). The common methods of RecordSet are: ①AddNew, create a new record; ②Cancel, cancel one execution; ③Close, close a record; ④Delete, delete a record or a group of records; ⑤MoveNext, move the record pointer to the next record.
11. In the UML model, the communication diagram is a kind of interaction diagram, also called collaboration diagram or communication diagram. It is a diagram that expresses the connection between objects and the sending and receiving of messages between objects.
13. The one-to-many relationship in UML class diagrams is represented by 1:*.
14. In the UML model, there are five views: structure, realization, behavior, environment, and use case views.
13 types of diagrams (UML2.0): static structure diagrams (class diagrams, object diagrams, package diagrams, deployment diagrams)
behavior diagrams (use case diagrams, interaction diagrams (sequence diagrams, communication diagrams...), state diagrams, activity diagrams)
inside the system The structure is generally divided into static structure and dynamic structure. Class diagrams are used to represent static structures, and sequence diagrams and communication diagrams are used to represent system dynamic structures. Sequence diagram emphasizes time, communication diagram emphasizes space.
A class diagram is a static view that shows a set of classes, interfaces, and protocols, and the relationships between them. It consists of three parts: class name, attribute, and operation.
Collaboration diagram (communication diagram) is a kind of interaction diagram, which displays the organizational interaction relationships and links between objects. Do not focus on the order of interaction, use the sequence number to determine the order of messages and their concurrent threads. It contains a set of objects, the connections between the objects, and the messages sent and received between the objects.
The state diagram is mainly used to describe the dynamic behavior of an object during its life, which is expressed as the sequence of states that an object experiences, the events that cause the state transition, and the actions that accompany the state transition. Generally, a state machine can be used to model the life cycle of an object. The state diagram is used to display the state machine, focusing on and describing the control flow of the state diagram.
The sequence diagram is mainly used to describe the message sending and receiving sequence between objects.
The deployment diagram describes the structure of the system at runtime, showing how the hardware configuration and software are deployed into the network structure. A system model has only one deployment diagram, which is usually used to help understand distributed systems.
Activity diagrams are mainly used to describe the sequential execution order and parallel order of logic flows in the system, use cases, and program modules.
Most suitable for describing the workflow of a system or subsystem. Activity diagrams can be operated in parallel, and flow charts can only be operated in series. An activity diagram can only have one start point and several end points.
Package diagram: A diagram used to express the relationship between different packages, namespaces or different projects in the system.
15. The four-layer modeling conceptual framework of UML semantics is:
①Metamodel layer: represents all things to be defined
②Metamodel layer: basic elements of UML, examples of "things" concept
③Model layer: UML model, Class model or type model
④User model layer: instance of UNL model, object model or instance model
16. In UML, aggregation is a special form of association, which represents the relationship between whole and part of classes.
19. The main purpose of the activity diagram is to state the transfer of process control between activities and activities. The purpose of the state diagram is to state the state transition of related events in the system.
20. The relationship between use cases includes expansion, use, and combination.
The use case model consists of three parts: use case, role and system. Roles are external entities that interact with the system, which can be system users or other systems or hardware devices.
21. The horizontal rectangular frame of the sequence diagram represents the object, and the horizontal message line is used to represent the communication between the objects. Sequence diagrams can be used to describe the creation and destruction of objects. There are two coordinate axes, the horizontal represents the object, and the vertical represents the continuous process of time.
22. Use case diagrams are used to describe the interaction between the system and external systems and users.
24. The use case model (outside the system) expresses the functional requirements of the system, that is, the expectations of users, through the description of system participants and their important behaviors.
25. The use case model is a tool that expresses all the functions that meet the needs of users.
27. A sequence diagram can represent a recursive process. When an operation calls itself, the message is always synchronized. Messages can have conditions, and it is stipulated that messages can be sent and received only when the conditions are true. If the conditions are mutually exclusive, the messages may be sent in parallel.
29. In UML, use cases are represented by ellipses, and use cases are located inside the system boundary.
32. In the state machine diagram, the transition between states is driven by events.
mind Mapping
