22.集合數組之間相互轉換

 

//7.集合轉數組
//https://www.cnblogs.com/goloving/p/7693388.html
//http://localhost:8000/dealConstant
@RequestMapping("/listToArray")
public  void  listToArray(){
    // list轉數組
   List<User> list = new ArrayList<>();
    User user = new User();
    user.setId(UUID.randomUUID().toString());
    user.setCreateTime(TimeUtils.getStringDate(new Date()));
    user.setSex("2");
    user.setName("測試1");
    list.add(user);
    //集合轉數組    注意數組類型
    User[] array=list.toArray(new User[list.size()]);
    System.out.println(array);
    //數組轉集合
    List<User> arrToList = Arrays.asList(array);
    System.out.println(arrToList);
}