Wildcard, wildcard upper, and lower bounds of wildcard characters

Wildcard:list<?> meaning is a List of elements of unknown type

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public void Test (list<?> c) {for (int i= 0; i<c.size (); i++) {System.out.println (C.get (i)      ); } }

Maximum wildcard character: list<? Extends shape> represents a subtype of shape or shape

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public  class  righttest {&NBSP;&NBSP;&NBSP;&NB Sp Static <T>  void  Test (collection<?  extends  t> from,collection<t>  to)      {         for (t ele:from)           {              To.add (ele);         }     }      public  static  void  Main (String[] args)      {          list<object> ao= new  arraylist<> ();          list<string> as= new  arraylist<> ();          test (AS,AO);     }}

Minimum wildcard character: list<? Super Type> represents the type itself or the parent class of type

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Package test;   Import java.util.*; public class Treesettest {public static void main (string[] args) {