What you should be able to do
- Separate state from action.
- Use event, guard and transition correctly.
03 / UML MODELING / L15
State Diagrams
A state diagram follows the life of one object, not the complete workflow of several actors.
How does one object change over time when events happen?
Terms to use precisely
Common mistakes
- Putting every system action into a state machine.
The same system needs different views.
Switch the question first. Then choose the diagram whose notation answers it.
DIAGRAM REVISION SHEETCurrent state: Draft
Event: submit → next state: Submitted
A state describes the condition of one object. An activity diagram describes a wider flow of work.
CHECKED LEARNING LINKS
Watch the part that solves the gap.
Each link is matched to this lesson. Start with a quick video when available. Open the full lecture when you need the academic explanation.