import java.util.ArrayList;
import java.util.Collections;
  public class Javacollectionexcercise {
  public static void main(String[] args) {
         ArrayList<String> Stringslist= new ArrayList<String>(3);
         Stringslist.add("Audi");
         Stringslist.add("BMW");    
         Stringslist.add("Bugatti");
          System.out.println("Original array list: " + Stringslist);
          //Increase capacity to 7
         Stringslist.ensureCapacity(7);
         Stringslist.add("Ford");
         Stringslist.add("Honda");
         Stringslist.add("Hyundai");
         Stringslist.add("Ferrari");
         System.out.println("New Increased array list: " + Stringslist);
   }
}

Result