jdk8 list是否包含某值的一些应用

memberList.forEach(aa -> {String householderRelation = aa.getHouseholderRelation();});

List<Map<String, String>> list = new ArrayList<>();
HashMap<String, String> map = new HashMap<>();
map.put("1","张三");
HashMap<String, String> map1 = new HashMap<>();
map1.put("1","李四");
HashMap<String, String> map2 = new HashMap<>();
map2.put("1","王五");
HashMap<String, String> map3 = new HashMap<>();
map3.put("1","赵六");
list.add(map);
list.add(map1);
list.add(map2);
list.add(map3);

boolean present = list.stream().filter(m -> "张三".equals(m.get("1").toString())).findAny().isPresent();//是否有户主
System.out.println(present);

boolean b1 = list.stream().anyMatch(task -> task.get("1").toString().equals("张三"));
System.out.println(b1);

List<Order> list = new ArrayList<User>();
Order o1 = new Order("1","MCS-2019-1123");
list.add(o1 );
Order o2= new Order("2","MCS-2019-1124");
list.add(o2);
Order o3= new Order("3","MCS-2019-1125");
list.add(o3);
List<String> orderNoList=list.stream().map(Order::getOrderNo).collect(Collectors.toList());
System.out.println("输出单号集合："+orderNoList);
List<String> idList=list.stream().map(Order::getId()).collect(Collectors.toList());
System.out.println(idList)