JAVA_ArrayList & Iterator

package java0416;
 
 
import java.util.ArrayList;
import java.util.Iterator;
public class test2 {
 
ArrayList<Integer> numList;
    public void Test2() {
        numList = new ArrayList<>();
        numList.add(100);
        numList.add(300);
        numList.add(400);
        for (Integer oNum : numList) {
            System.out.println(oNum);
        }
        
        numList.add(1,200);
        Iterator<Integer>  iNum= numList.iterator();
        while(iNum.hasNext()) {
            System.out.println(iNum.next());
        }
 
        
    }
    
}