java list iterator

Question

I'm writing a code to have 2 lists of integers and iterators for each one. Second one is constructed as reversed first one.

I have a problem with displaying values of the second one using iterator. How to fix that (note that I have used simple for iteration and it works, but want to do it with iterator).

import java.util.*;

public class Ch11Ex12 {
      public static void main(String[] args) {

            List<Integer> li = new ArrayList<Integer>();
            li = Arrays.asList(1, 6, 4, 7);
            //List<Integer> li2 = new ArrayList<Integer>();
            int z = li.size();
            List<Integer> li2 = new ArrayList<Integer>();

            /**
            for (int index = 0; index < ints.length; index++)
            {
                li.add(ints[index]);
            }
            **/
            ListIterator<Integer> it = li.listIterator(z);
            ListIterator<Integer> it2 = li2.listIterator();         
            while(it.hasPrevious()){
                //System.out.print(it.previous() + " ");
                int k = it.previous();
                System.out.print(k + " ");
                li2.add(k);
            }
            /**
            for (int f = 0; f < li2.size(); f++){
                System.out.println(li2.get(f));
            }
            **/
            while(it2.hasNext()){
                int p = it2.next();
                System.out.print(p + " ");
            }       
     }
}

Answer 1

Define your second Iterator it2 after having filled li2.

        ListIterator<Integer> it = li.listIterator(z);       
        while(it.hasPrevious()){
            //System.out.print(it.previous() + " ");
            int k = it.previous();
            System.out.print(k + " ");
            li2.add(k);
        }

        /**
            Now that I have filled li2, I create my ListIterator it2.
        **/
        ListIterator<Integer> it2 = li2.listIterator();  
        while(it2.hasNext()){
            int p = it2.next();
            System.out.print(p + " ");
        }