Let’s say the following is our Collection i.e. ArrayList −
List<Integer>list = new ArrayList<Integer>(); list.add(100); list.add(200); list.add(200); list.add(200); list.add(300); list.add(400); list.add(400); list.add(500);
Now, create another Collection −
List <Integer>list2 = new ArrayList<Integer>(); list2.add(100); list2.add(200); list2.add(300); list2.add(400);
To remove all elements from a Collection in another Collection, try the following with list and list2 as our two Collections −
list.removeAll(list2);
import java.util.ArrayList; import java.util.List; public class Demo { public static void main(String args[]) throws Exception { List<Integer>list = new ArrayList<Integer>(); list.add(100); list.add(200); list.add(200); list.add(200); list.add(300); list.add(400); list.add(400); list.add(500); List <Integer>list2 = new ArrayList<Integer>(); list2.add(100); list2.add(200); list2.add(300); list2.add(400); list.removeAll(list2); System.out.println("Resultant list = "+list); } }
Resultant list = [500]