List三种循环方式

public static void main(String[] args) {   List<String> list=new ArrayList<String>();   list.add("123");   list.add("456");   list.add("789");   System.out.println("------经典的for循环-----");   for (int i = 0; i < list.size(); i++) {       System.out.println(list.get(i));   }   System.out.println("-------Iterate循环--------");   Iterator<String> iter=list.iterator();   while(iter.hasNext())   {       System.out.println(iter.next());   }   System.out.println("-------foreach循环---------");   for (String string : list) {     System.out.println(string); }}