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Sequence diagram deleteGraph
The crewmember deletes a graph on the webpage. the front-end does a call to the back-end. The resource is only responsible for returning the response so it gets delegated to GraphService. The GraphService delegates this to the GraphDAO because deleting the data from the database is not the responsibility of the service. In the GraphDAO the graph gets deleted from the database. The benefit of this structure is that you can easily swap the classes which results in low cohesion and high coupling. This structure is based of the the layer pattern.
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