java - Getting to the subclass from superclass objects list -


I have a class, say - animal . And some sections that inherit from it, we say: birds , cat , dog .

Now let me add an array of animal types, and some examples of its sub-classes. 

  Private list & gt; Animals & gt; List = New Arrestist & lt; Animals & gt; (); List.add (new bird ()); list.add (new bird ()); List.add (new cat ()); List.add (new dog ());   
 Then I repeat through this list, call some methods, etc.  
 for  (int i = 0; i   
 OK. But what if I would like to add a  bird  method, which will not be applied in the  animal  superclass? Suppose,  fly ()  method, then it looks like this:  
 for  (int i = 0; i & lt; list.length; i + +) {List .Get (i) .makeSound (); If (list.get (i) breed example) {list.get (i) .fly (); // error here}}   
 This makes sense, but it throws an error - the symbol can not be found  animal  in the class to implement this method It seems to solve this issue, but I have to do this many times when there is pain in my eyes, is there any way to solve this issue?   
 
 
 You  cast >:  
  (Bird) list.get (i)). Fly ();

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