| Previous | UML Classes | Table of Contents | UML Packages | Next | 
   • 
   
               Dependency	    (from Dependencies	   ) on page 61 
               
   A usage is a relationship in which one element requires another element (or set of elements) for its full implementation or
               operation. In the metamodel, a Usage	    is a Dependency	    in which the client requires the presence of the supplier. 
   No additional attributes 
   No additional associations 
   No additional constraints 
   The usage dependency does not specify how the client uses the supplier other than the fact that the supplier is used by the
               definition or implementation of the client. 
   A usage dependency is shown as a dependency with a «use» keyword attached to it. 
   In the example below, an Order class requires the Line Item class for its full implementation. 

   Figure 7.75 - An example of a use dependency