/** * Copyright (C) 2010-2017 Gordon Fraser, Andrea Arcuri and EvoSuite * contributors * * This file is part of EvoSuite. * * EvoSuite is free software: you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as published * by the Free Software Foundation, either version 3.0 of the License, or * (at your option) any later version. * * EvoSuite is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with EvoSuite. If not, see <http://www.gnu.org/licenses/>. */ package com.examples.with.different.packagename.generic; import java.util.ArrayList; import java.util.HashSet; import java.util.List; public class GenericCollectionUtil { public static <E> List<E> intersection(final List<? extends E> list1, final List<? extends E> list2) { final List<E> result = new ArrayList<E>(); List<? extends E> smaller = list1; List<? extends E> larger = list2; if (list1.size() > list2.size()) { smaller = list2; larger = list1; } final HashSet<E> hashSet = new HashSet<E>(smaller); for (final E e : larger) { if (hashSet.contains(e)) { result.add(e); hashSet.remove(e); } } return result; } }