UML - Object Method Returns a Collection

Question

How can I indicate that a method will return a collection of objects in UML? Is there a better way to explain the relationship than to have a collection class as a return type?

Answer 1

I am coming to this a little late, since I was looking for an answer to a similar question. I am writing this incase somebody else is looking for a similar answer.

Do you want to indicate that a method returns a collection of a specific type? If so, for a method you should be able to set the type of the return parameter and the multiplicity of the return parameter to 0..* or 1..*. This would indicate that the method returns the specified type and that it has whatever multiplicity you state.

E.g. using the Library <>--- Book example, suppose there is a method on Library called GetBooks that takes a string parameter, author name, and returns a collection of Book instances. The UML would look something like this:

Library +GetBooks(authorName: string) : Book[0..*]

Your UML diagramming tool should support this; I am using Magic Draw. This UML states that GetBooks returns 0 or many Book instances. It is now up to programmer to decide how to implement the return parameter in the implementation language (as stated above by Simon).