com.javarush.task.task35.task3506

Solution.java

package com.javarush.task.task35.task3506;

import java.util.ArrayList;
import java.util.List;
import java.util.ListIterator;

/*
Wildcards
*/
public class Solution
{

    public static <D, H extends D, S extends H> void add1(List<D> destinationList, List<S> sourceList)
        {
        ListIterator<D> destListIterator = destinationList.listIterator ( );
        ListIterator<S> srcListIterator  = sourceList.listIterator ( );
        for (int i = 0; i < sourceList.size ( ); i++)
            {
                destListIterator.add (srcListIterator.next ( ));
            }
        }

    public static <T> void add(List<? super T> destinationList, List<? extends T> sourceList)
        {
        ListIterator<? super T>   destListIterator = destinationList.listIterator ( );
        ListIterator<? extends T> srcListIterator  = sourceList.listIterator ( );
        for (int i = 0; i < sourceList.size ( ); i++)
            {
                destListIterator.add (srcListIterator.next ( ));
            }
        }


    public static void main(String[] args)
        {
        List<B> destination = new ArrayList<> ( );
        destination.add (new B ( ));
        List<C> source = new ArrayList<> ( );
        source.add (new C ( ));
        add (destination, source);
        System.out.println (destination);
        System.out.println (source);

        /*
[com.javarush.test.level39.lesson08.task01.Solution$C@203b4f0e, com.javarush.test.level39.lesson08.task01.Solution$B@15c330aa]
[com.javarush.test.level39.lesson08.task01.Solution$C@203b4f0e]
         */
        }

    static class A
    {
    }

    static class B extends A
    {
    }

    static class C extends B
    {
    }
}