java-stream-根据某个字段去重
public static void main(String[] args) { List<User> userList = new ArrayList<>(); userList.add(new User("1","李大锤","23","南京")); userList.add(new User("2","张无忌","18","西安")); userList.add(new User("3","刘德华","26","苏州")); userList.add(new User("4","郭靖","33","上海")); userList.add(new User("1","李大锤","23","南京")); userList.add(new User("3","带头大哥","36","杭州")); System.out.println("原数据"+userList); userList = userList.stream()
.collect(Collectors.collectingAndThen(Collectors
.toCollection(()->new TreeSet<>(Comparator.comparing(User::getId))), ArrayList::new)); System.out.println("现数据"+userList); } 原数据:[User(id=1, username=李大锤, password=23, address=南京), User(id=2, username=张无忌, password=18, address=西安), User(id=3, username=刘德华, password=26, address=苏州), User(id=4, username=郭靖, password=33, address=上海), User(id=1, username=李大锤, password=23, address=南京), User(id=3, username=带头大哥, password=36, address=杭州)]
去重后的数据:[User(id=1, username=李大锤, password=23, address=南京), User(id=2, username=张无忌, password=18, address=西安), User(id=3, username=刘德华, password=26, address=苏州), User(id=4, username=郭靖, password=33, address=上海)]