java - Generic class initialization -


this class:

public class foodset<t extends concretefood>{     public list<t> food = new arraylist<t>();     public foodset()     {         /*         *  foodtype enum containing food types e.g: rice, pork, beef ...         */         for(foodtype foodtype : foodtype.values())         {               /*             * 1(*)             * /             food.add( (t)new concretefood(foodtype,0) )          }            } }

and in 1(*) problem, how init list, 't' type ? init concretefood, giving argument foodtype , amount, goal init list t extends concretefood. every subclass of concretefood has access foodtype , food count. init list apropriate concretefood subclass , init each concretefood object foodtype , count = 0. how should ?

this isn't want. need factory class create instances of concretefood you.

public class foodfactory {     private static final foodfactory instance = new foodfactory();      private foodfactory() {}      public static foodfactory getinstance() { return instance; }      public food create(foodtype type) {        // put type checks here      } }

i don't care naming much. "concretefood"? doesn't sound appetizing. why not foodcategory?


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