MarbleCollection

package com.company;
import java.util.ArrayList;
    public class MarbleCollection {
        private ArrayList<MarbleSet> sets;

        public MarbleCollection() {
            sets = new ArrayList<MarbleSet>();
        }

        public void addSet(MarbleSet theset) {
            sets.add(theset);
        }

        public int getTotalMarbles() {
            int total = 0;
            for (MarbleSet i : sets) {
                total += i.getNumber();
            }
            return total;
        }

        public int removeColor(String marbleColor) {
            int total = 0;
            for (MarbleSet i : sets) {
                if (i.getColor().equals(marbleColor)) {
                    total += i.getNumber();
                    sets.remove(i);
                }
            }
            return total;

        }
    }
}