Java tutorial
//package com.java2s; //License from project: Open Source License import java.util.ArrayList; import java.util.Collection; public class Main { public static <T> ArrayList<T> inter(Collection<T> l1, Collection<T> l2) { ArrayList<T> l = new ArrayList<>(); for (T e : l1) { if (l2.contains(e)) { l.add(e); } } return l; } }