inheritance - How does the java compiler know of inherited methods? -


we use inheritance in java abstract out similar behavior in superclass , let sub classes inherit it. 1 of advantages of , have 1 copy of method maintain (i.e in superclass).

class animal {    public void makenoise()    {     }     public void sleep()    {     }    }   class cat extends animal {      // override makenoise method      public void makenoise()      {       } }  class someclass {      public static void main(string args[])      {           cat fluffy = new cat();            fluffy.sleep();      } }

i trying understand how java compiler knows of sleep() method cat type reference. there can't copy of method in cat subclass (it defeats purpose of having in superclass , letting subclasses inherit it). information stored in other place ?

when compiler sees fluffy.sleep() first looks in cat class public instance method called sleep takes no parameters. since doesn't find it, moves inheritance chain animal, , same check on animal. finds there, good.

this information isn't "stored" anywhere except in code, , java byte code.


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