Program 2 to explain Generic method with Bounded type in Java

// Program to explain Generic method with Bounded type.
// GenericType<? extends upperBoundType>
import java.util.ArrayList;
import java.util.List;
public class  GenericTest10 
{
public static double getAverage(List<? extends Number> numberList) 
{
 double total = 0.0;
 for (Number number : numberList) 
 {
  total += number.doubleValue();
 }
 return total / numberList.size();
}
public static void main(String[ ] args) 
{
 List<Integer> iList = new ArrayList<Integer>();
 iList.add(3);
 iList.add(30);
 iList.add(300);
 System.out.println(getAverage(iList)); 
 
 List<Double> dList = new ArrayList<Double>();
 dList.add(3.0);
 dList.add(33.0);
 dList.add(333.0);
 System.out.println(getAverage(dList)); 
}
}

Output:
111.0
123.0