use case diagram - conditions or decision node

Question

guys how can I make conditions in use case diagram ? Something like decision node in activity diagram.

For example, If there is "evaluate" usecase which can lead either to Y or N, there is simply no way to express it. There is only constrain feature, that would lead to repeating { if evaluated } {if evaluated } ......

Answer 1

What you probably want to use is alternative paths, basically what you do is you repeat part of your use case like this:

In step 5, if there is not enough money on the account

1. 5.a Show a message to the user
2. 5.b User press "Try a lesser amount" button
3. 5.c System goes to step 3

Answer 2

The Use Case Diagram doesn't seem to fit at all with conditions. Usually, when depicting multiple scenarios, one would make multiple use cases for each one. An activity diagram would be more fitting to display conditional logic.

Answer 3

Usually, conditions (IF) exist somewhere in the use case's activity that would cause the extended use case to occurs. You can add to extended use case to represent yes/no scenarios.