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import java.util.ArrayList;
import java.util.HashSet;

/*
 * Example of removeAll(Collection<? extends E> c) method.
 */
public class HashSetExample
{
    public static void main( String[] args )
    {
        HashSet<String> hashSet = new HashSet<String>();

        hashSet.add("Rohan");
        hashSet.add("Phil");
        hashSet.add("Ram");
        hashSet.add("Dave");
        hashSet.add("Peter");

        System.out.println("hashSet : " + hashSet + "\n");

        ArrayList<String> arrayList = new ArrayList<String>();
        arrayList.add("Ram");
        arrayList.add("Dave");
        arrayList.add("Peter");

        System.out.println("arrayList : " + arrayList + "\n");

        /*
         * Removes from this set all of its elements that are contained in the
         * specified collection.
         */

        boolean isRemoved = hashSet.removeAll(arrayList);

        System.out.println("isRemoved : " + isRemoved);
        System.out.println("hashSet : " + hashSet + "\n");

    }
}