Article directory
Object-oriented modeling basics
UML modeling language
1. Why does system development require modeling?
In the real world, information systems are usually complex systems. In order to develop and implement information systems, it is necessary to abstract a set of models that reflect the most essential aspects of the system. In this way, the details can be omitted, and the substantive analysis and description of the information system can be achieved and the system design can be simplified to a certain extent. A model is therefore a simplified description of the real world.
2. The role of system model
- Helps provide a visual representation of the system to be developed in the desired style
- Models can reflect the structure and behavior of a system
- Models provide templates for constructing systems
- Models serve as documented design decisions
3. Principles of system modeling
- Choose the right modeling method
- Provide different levels of abstraction models
- Create different view models from multiple perspectives
- The model should accurately depict the static structure and dynamic behavior of the system
4. Introduction to UML modeling language
- UML (Unified Modeling Language) is an object-oriented visual modeling language.
- UML is a universal standard modeling language that can model the static structure and dynamic behavior of the system.
- UML can be used for modeling at different stages of system development, such as from system requirements analysis to system testing and maintenance.
- UML contains two major types of model diagrams that describe the static structure and dynamic behavior of the system, with a total of 14 types of graphics.
UML model diagram
use case diagram
Use case diagram model elements:
System Use Case Diagram is a model diagram that describes the system requirement functions from the perspective of a system analyst .
- Use cases are the functional point abstractions of the system .
- Roles are user type abstractions for the system .
- The association between roles and use cases, use cases and use cases means that they have a certain connection.
Business Use Case Diagram is a model diagram that describes business functions from the user's perspective .
- Use cases are functional point abstractions of the business .
- Roles are user type abstractions for the business .
- The association between roles and use cases, use cases and use cases means that they have a certain connection.
activity diagram
Activity diagram model elements:
Activity Diagram is a model diagram that describes the execution sequence of activities within a use case and the input and output of activities.
Activity diagrams can also be used to describe business processes, algorithm processes, system control processes, etc.
Class Diagram
Class diagram model elements:
Class Diagram describes which classes the system is composed of, that is, it is composed of object-oriented programs.
It is also used to describe the relationship between class programs in the system and visually present the static structure of the system program.
Flowchart
Sequence diagram model elements:
Sequence Diagram (also called sequence diagram) is a model diagram that describes message interaction between objects.
It is used to reflect the dynamic collaboration relationship between objects, that is, the interactive relationship between objects.
communication diagram
Communication diagram model elements:
Communication Diagram is a model diagram that expresses direct message interaction relationships between objects.
It shows how multiple objects communicate with each other while working together to achieve a common goal.
The interactive relationship between objects is displayed through objects and links between objects and messages sent.
State machine diagram
State machine diagram model elements:
State Machine Diagram is a model diagram that describes the various states and state changes that an object experiences during its life cycle.
Describes all possible states of objects of a class and the transition conditions of states when events occur.
Component diagram
Assembly diagram model elements:
Component diagram (Component Diagram) is a model diagram that describes the components of the system and their relationships.
Describe the physical structure of software implementations, thus reflecting component-based software implementations.
Deployment diagram
Deployment diagram model elements:
Deployment Diagram represents the deployment plan of system components in the running environment nodes.
The physical topology between software and hardware nodes, processing nodes, and operating environment can also be obtained from the deployment diagram.
Package map
Package diagram model elements:
Package Diagram (Package Diagram) is an organizational structure model diagram that uses package symbols similar to folders to represent model elements. Packages are described as folders and can be applied to any kind of UML diagram.
Every element in the system can only be owned by one package, and a package can be nested within another package.
object graph
Object Diagram (Object Diagram) shows how instances of class elements are related and how they are used at runtime.
Like the class diagram, the UML object diagram reflects the static structure of the system, but the object diagram is expressed from the instantiation scenario, and it shows the relationship between objects at a certain moment.
Combined structure diagram
Composite Structure Diagram (CompositeStructure Diagram) provides a method for modeling the internal structure of system components, and also describes the interaction points between this component and other components of the system.
Internal components interact with the environment through ports. Cooperation between internal components.
Extended diagram
The extension diagram (Profile Diagram) provides a lightweight UML extension mechanism (stereotypes, tagged values, constraints, base classes, etc.) for specific domains.
Define a set of constructs with domain-specific attributes and constraints, thereby extending the underlying UML elements.
Interactive overview diagram
Interaction Profile Diagram (Profile Diagram) is a hybrid of Interaction Diagram and Activity Diagram.
Provides the interaction between objects described in complex activity process nodes.
time graph
Time Diagram (Time Diagram) is used to model the time-series state change relationship between objects.
Also express time and deadline constraints for interactions between objects.
BPMN modeling language
business modeling
Business Modeling (Business Modeling, BM) is a business model that describes the object elements involved in organizational management and its business, as well as their behavioral relationships, and provides a basis for continuous improvement of business processes.
Business modeling content :
- Organization modeling
- Department function modeling
- business process modeling
- Business Information Data Modeling
Relationships between business model diagrams :
definition
BPMN (Business Process Modeling Notation) defines a standard set of business process flow notation, which can be used to create a graphical model describing the operation of business processes.
BPMN also supports the generation of executable Business Process Execution Language (BPEL). BPMN can be converted into software process components based on WS-BPEL. BPMN can be used to model and describe the organization's internal business process capabilities, and its model can be used as a bridge for designers, managers and business process personnel to communicate business activities.
model elements
stream object
Activity
Activity: refers to any work performed in the process, that is, tasks.
event
Event: Anything that happens in a business process.
gateway
Gateway: A branch used to control the process.
flow
Flow is used to connect flow objects and define the process of business processes together with flow objects.
data
Data refers to the data representation in business processes, which is divided into data objects, data object sets, data input and data output , etc.
Man-made production
Artifacts are used to represent processes with additional information to support the process description of business processes.
Pools and lanes
Pool identifies the activities and process scope of each entity participant in the business. A swimming pool can contain multiple lanes.
Modeling case
Order procurement process modeling
E-commerce system ordering business process modeling
Shipping business process modeling for a hardware retailer
Both UML modeling and BPMN modeling can use modeling tools Power Designer and Enterprise Architecture.
Class exercises
1. Which of the following is not a concept in object-oriented thinking? (B)
A．encapsulationB．Contains C．PolymorphismD．abstract
2. UML structure diagram does not contain which of the following diagrams? (A)
A．Use case diagram B. Class diagram C. Component diagram D. deployment diagram
3. Which of the following elements does a class diagram contain? (D)
A．Class B．relationshipC. interface D．All of the above
4. Which of the following elements does a sequence diagram not contain? (A)
A．Lane B. Object C. News D. lifeline
5. The model is (A)
A．Simplified description of the real world
B. A complete description of the real world
C．concrete description of the real world
D．real world encapsulation
1. Object-oriented requirements analysis is programming language agnostic. (√)
2. Activity diagrams can represent concurrent activities. (√)
3. Each state machine diagram can reflect the state of multiple objects. (×)
4. Components can be embedded in the nodes of the deployment diagram. (√)
5. BPMN can be converted into software process components based on WS-BPEL. (√)
6. The state machine diagram has self-conversion states. (√)
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The application of object-oriented thinking includes object-oriented analysis, (object-oriented design), and object-oriented programming.
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The relationships between classes in the class diagram include association relationships, dependency relationships, aggregation relationships, (generalization relationships).
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The elements in the communication diagram include objects, (messages), chains, and reflexive chains.
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BPMN flow objects are divided into three categories: activities, (events), and gateways.
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Data in BPMN is divided into data objects, (data object sets), data input and data output, etc.