List Collection index traversal and iterator traversal in Java

Package Yzhou.iterator;import Java.util.arraylist;import java.util.hashset;import java.util.iterator;import Java.util.list;import Java.util.Set; Public classtest01{ Public Static voidMain (string[] args) {List List=NewArrayList (); List.add ("AAA"); List.add ("BBB"); List.add ("CCC"); //Traverse list by index         for(intI=0; I<list.size (); i++) {System. out. println (list.Get(i)); }                //Iterating through the list through an iterator         for(Iterator iter2 =list.iterator (); Iter2.hasnext ();) {String str=(String) iter2.next (); System. out. println (str);        Iter2.remove (); } System. out. println (List.size () +"************************************"); SetSet=NewHashSet (); Set. Add ("Zhangsan1"); Set. Add ("zhangsan2"); Set. Add ("zhangsan3"); //Iterator iter = Set.iterator ();//While (Iter.hasnext ())//        {//string str = (string) iter.next ();//System.out.println (str);//        }                 for(Iterator iter =Set. iterator (); Iter.hasnext ();) {String str=(String) iter.next (); System. out. println (str); }    }}

Separately:

 for Set . iterator (); Iter.hasnext ();)        {            = (String) Iter.next ();            System.  out . println (str);        }

This is for and iterator.

For the execution steps:

Initialize values First

Judge

Executing function body

Assignment ++/--

Judge

Executing function body

......

List Collection index traversal and iterator traversal in Java