Finding the different elements between two ArrayLists in Java

Question

How can I know the different element between 2 array list in java? I need the exact element not a Boolean value which can be retrieved using removeAll().

Answer 1

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

public class CompareTwoList {
    public CompareTwoList() {
        // TODO Auto-generated constructor stub
    }

    public static void main(String[] args) {
        List ls1 = new ArrayList();
        ls1.add("a");
        ls1.add("b");
        ls1.add("c");
        ls1.add("d");

        List ls2 = new ArrayList();
        ls2.add("a");
        ls2.add("b");
        ls2.add("c");
        ls2.add("d");
        ls2.add("e");

        Set set1 = new HashSet();
        set1.addAll(ls1);

        Set set2 = new HashSet();
        set2.addAll(ls2);
        set2.removeAll(set1);

        //set.addAll(ls1);
        //set.addAll(ls1);

        for (String diffElement : set2) {
            System.out.println(diffElement.toString());
        }
    }
}