Generics Type issue
- by JohnJohnGa
ArrayList<Integer> arrI = new ArrayList<Integer>();
ArrayList arrO = arrI; // Warning
/* It is ok to add a String as it is an ArrayList of Objects
but the JVM will know the real type, arrO is an arrayList of
Integer...
*/
arrO.add("Hello");
/* How I can get a String in an ArrayList<Integer> ??
Even if the compiler told me that I will get an Integer!
*/
System.out.println(arrI.get(0));
Anybody can explain what's happening here?
