UML object class diagram

The object class diagram of UML can be better usedDatabaseModeling. Traditional E-R diagram only focus on data, while UML object class diagram not only on the data, but also on the behavior modeling, these behavior in the physical database is designed as a trigger and storageProcess. For relational databasesSystemYou can use an object class diagram to describe the database mode and a class to describe the database tables. For an object database system, you can use an object class diagram to directly describe the object classes in the database.

Interaction diagram:
Interactive charts form interactions between objects. They describe how a group of objects collaborate to complete a behavior.ModelInformatizationTools. It is mainly usedControlStream modeling. It can effectively help people observe and understand the cooperative relationship and process behavior in the system. There are two types of UML interaction diagrams: Sequence Diagram (similar to sequence diagram) and collaboration diagram. The sequence diagram focuses on message exchange of objects in chronological order, and the Collaboration diagram focuses on how system components work collaboratively.

The Order chart and the collaborative graph are both Interactive graphs, which are equivalent and different.
The sequence diagram and the Coordination diagram both show the interaction behavior of objects through messages in the system operation.
The sequence diagram shows the time message sequence, which facilitates analysis of the interaction sequence, but does not represent the static object relationship. Sequence graphs can effectively help people observe the ordered behavior of the system.
A collaboration diagram focuses on the relationship and messages between objects in a collaboration. A collaboration diagram is used to describe the implementation of an operation or a classifier and is often used to help design a behavior.
When establishing a behavior model for the system, the most typical practice is to model the control flow in chronological order using a sequence chart, and to model the control flow in an object organization using a collaboration diagram.

Status chart:
The UML state chart is mainly used to establish a dynamic behavior model of an object class or object, representing the sequence of states that an object experiences, events that cause state or activity transfer, and actions that are accompanied by status or activity transfer. It is represented by a state machine. The status chart and activity chart can be expressed in two ways. The state chart focuses on establishing a model for the possible states and their transfer of a model element, focusing on the control flow from one state to another. The activity diagram focuses on creating a model for the control flow from one activity to another.
The status chart and the Interaction chart have different focuses: The Interaction chart indicates that several objects work together to complete a service, while the state chart is a model for the condition of an object during its lifecycle.
The status chart and activity chart are different. Activity diagrams describe the sequence of activities and model the control flow from activities to activities. They are suitable for expressing workflow and concurrent processing. The state chart expresses the state machine, which is used to model the control flow from events to events. A state chart can indicate the history of an object, events that cause a state to be transferred to another State, and actions that result from state transfer.
A state chart is suitable for describing the behavior of an object traversing multiple use cases, but a state chart is not suitable for describing the collaborative behavior of multiple objects.
A state chart can be used to model an object (class), or to model the behavior of a sub-system or the entire system.

An activity diagram is a tool used for modeling system behaviors. It supports the description of concurrent behaviors. Features Makes it a powerful tool for modeling workflows, especially suitable for MultithreadingProgram. One major drawback of an activity diagram is that the connection between an action and an object is unclear. The activity diagram can be used in the following situations:
① Analyze use case;
② Understanding work Process ;
③ Describe complex processAlgorithm;
④ Processing Multithreading Application .

the difference between an activity chart and a state chart: An activity chart focuses on responding to the actions of an object class processed internally. A state chart describes the external actions of an object class RESPONSE event; the activity diagram focuses on the control flow from one activity to another and is an internal processing-driven process. The state diagram focuses on the process from one state to another, it is often used when asynchronous events occur.