can someone help ? were usung java , attach comments , code text and the screenshot please

7. Write a method countCommon that accepts two lists of integers as parameters and re- turns the number of unique integers that oc- cur in both lists. Use one or more sets as storage to help you solve this problem. For example, if one list contains the values [3, 7, 3, -1, 2, 3, 7, 2, 15, 15] and the other list contains the values [-5, 15, 2, -1, 7, 15, 36], your method should return 4 because the elements 1, 2, 7, and 15 occur in both lists