java - What is the best way to convert relational to object oriented? -

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since learned rdbms, started thinking in relational model , less in object oriented. i'm having trouble trying store , query data in java data structures.

i want write application has entity sets relate each other made each entity own class. attributes each entity instance variables. okay think we're far. title , game entities. game isa title title should parent class , game should inherit title (think of game physical copy , title name of game).

i have set of games in main class , can iterate through if want find specific game. how find specific title? don't have set of titles because title inherited assume should iterate through games , when find name of title, add set unique titles back.

game mutable (isbought can change) using set bad idea? best way create entity sets in java? using map instead of set map id object?

fixing object-relational gap not easy task. there orm (object-relational mapping) frameworks that. have learning curve. hibernate , eclipselink 2 implementations of orm standard in java - jpa (java persistance api).


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