// copying lists need to have the destination size to be 
    // the same or bigger than the source size

import java.util.ArrayList;
import java.util.Collections;
import java.util.Vector;

public class g {

    public static void main(String[] args) {
        ArrayList<String> al = new ArrayList<String>();
        al.add("1");  al.add("2"); al.add("3"); al.add("4"); al.add("5");
        Vector<String> v = new Vector<String>();
        for(String s:al){v.add(null);}
        System.out.println(v);
        Collections.copy(v, al);
        System.out.println(v);
    }
}


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// backup before using the set command
import java.util.*;

public class r {

    public static void main(String[] a) {
        ArrayList<String> al = new ArrayList<String>();
        al.add("1");
        al.add("2");
        al.add("3");
        System.out.println(al);

        Vector<String> v = new Vector<String>();
        for (String s:al) {v.add(null);}
        Collections.copy(v, al);


        al.set(0, "4");
        al.set(1, "5");
        al.set(2, "6");

        System.out.println(al);

        System.out.println("But Still you have the old ones ---------");
        System.out.println(v);
    }
}

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