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The crewmember goes to the rewatch race page where the front-end does a call to the back-end. This activates the getAllRaces method in the RaceResource. The resource is only responsible for returning the response so it gets delegated to the RaceService, because the resource is not allowed to have any logic in it. The RaceService decides the flow, that is why he is the controller. The RaceService delegates this to the raceDAO because getting the data from the database is not the responsibility of the service. In the RaceDAO a database connection is established to get all the data 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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