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javaumlclass-diagram

How to express dependency in a UML Class Diagram?

I the following two classes:

class a {
    void foo(){
        b object= new b();
        object.baar();
    }
}
class b {
    void baar(){
    }
}

How to express class a using class b with Class Diagram (which arrow to use)?

Solution

  • Whenever one class has a reference/uses another, it is said to have a dependency on it. In your example, class a uses class b. Therefore class a has a dependency on class b. For that, you can use the UML dashed line with open arrow as described here.

    This is a very general relationship.

    One class depends on another if the independent class is a parameter variable or local variable of a method of the dependent class.

    If your class a had an instance variable, you would use the association link instead.