Java iterator listiteator

Import Java. util. *; class animal {string name; int age;} public class list {public static void main (string ARGs []) {arraylist list = new arraylist (); list. add (1); list. add (2); list. add (3); list. add (4); list. add (5); list. add (6); // use iterator to traverse arraylist // list. remove (object) 3); For (iterator it = List. iterator (); it. hasnext ();) {system. out. println (it. next ();} * directly use listiterator to traverse the arraylist; * For (listiterator it = List. listiterator (); it. hasnext ();) {system. out. println (it. next ();} * // use iterator to delete data * For (iterator it = List. iterator (); it. hasnext ();) {If (it. next () = (object) 4) {It. remove () ;}for (iterator it2 = List. iterator (); it2.hasnext ();) {system. out. println (it2.next ();} Use listiterator to add the element for (listiterator it = List. listiterator (); it. hasnext ();) {If (it. next () = (object) 3) {It. add ("three") ;}}for (listiterator it2 = List. listiterator (); it2.hasnext ();) {system. out. println (it2.next ();} For (listiterator it = List. listiterator (); it. hasnext ();) {It. add ("add"); it. next () ;}for (iterator it2 = List. iterator (); it2.hasnext ();) {system. out. println (it2.next ();} * // system. out. println (list. descendingiterator () ;}}/** note: During the iteration process, container operations cannot be added. modify. delete operation. this will cause concurrent operation exceptions, because the elements cannot be changed by means other than the iterator during the iterator iteration process, therefore, you can only use the method in the iterator to modify the container. Therefore, the following operation may encounter an error * For (iterator it = List. iterator (); it. hasnext ();) * {* If (it. next (). equals ("ABC") * List. add ("def"); // This will show *} * use listiterator to add the element * For (listiterator it = List. listiterator (); it. hasnext ();) * {* If (it. add ("google") // you may have added *} ***** 7:57:39 **/