JAva 8 2つのList集合は、交差、並列、差分、デマルチプレクサをとる

public static void main(String[] args) {
    List list1 = new ArrayList();
    list1.add("1");
	list1.add("2");
	list1.add("3");
	list1.add("5");
	list1.add("6");
 
    List list2 = new ArrayList();
    list2.add("2");
	list2.add("3");
	list2.add("7");
	list2.add("8");
 
    //   
    List intersection = list1.stream().filter(item -> list2.contains(item)).collect(toList());
    System.out.println("---   intersection---");
    intersection.parallelStream().forEach(System.out :: println);
 
    //    (list1 - list2)
    List reduce1 = list1.stream().filter(item -> !list2.contains(item)).collect(toList());
    System.out.println("---   reduce1 (list1 - list2)---");
    reduce1.parallelStream().forEach(System.out :: println);
 
    //    (list2 - list1)
    List reduce2 = list2.stream().filter(item -> !list1.contains(item)).collect(toList());
    System.out.println("---   reduce2 (list2 - list1)---");
    reduce2.parallelStream().forEach(System.out :: println);
 
    //   
    List listAll = list1.parallelStream().collect(toList());
    List listAll2 = list2.parallelStream().collect(toList());
    listAll.addAll(listAll2);
    System.out.println("---   listAll---");
    listAll.parallelStream().forEachOrdered(System.out :: println);
 
    //     
    List listAllDistinct = listAll.stream().distinct().collect(toList());
    System.out.println("---       listAllDistinct---");
    listAllDistinct.parallelStream().forEachOrdered(System.out :: println);
 
    System.out.println("---   List1---");
    list1.parallelStream().forEachOrdered(System.out :: println);
    System.out.println("---   List2---");
    list2.parallelStream().forEachOrdered(System.out :: println);
 
}