List对象 交集 并集 差集 判断及 属性多值 相同不同 判断

List<StudentDTO> oldList = Arrays.asList(
        new StudentDTO(111, "aaa", 16, "123@163", "123"),
        new StudentDTO(222, "bbb", 18, "123@163", "456"),
        new StudentDTO(666, "fff", 20, "123@163", "999")
);

List<StudentDTO> newList = Arrays.asList(
        new StudentDTO(111, "aaa", 16, "123@163", "123"),
        new StudentDTO(222, "bbb", 18, "123@163", "456"),
        new StudentDTO(333, "ccc", 19, "123@163", "789")
);

@Test
public void test() {
    //根据名字交集 111 222
    List<StudentDTO> andList = newList.stream()
            .filter(item -> oldList.stream()
            .map(e -> e.getName()).collect(Collectors.toList()).contains(item.getName()))
            .collect(Collectors.toList());

    System.out.println(andList);
}
@Test
public void test2() {
    //差集oldList-oldList 666
    List<StudentDTO> list = oldList.stream()
            .filter(item -> !newList.stream().map(e -> e.getName()).collect(Collectors.toList()).contains(item.getName()))
            .collect(Collectors.toList());

     System.out.println(list);
}
@Test
public void test3() {
      //差集newList-oldList 333
    List<StudentDTO> list = newList.stream()
            .filter(item -> !oldList.stream().map(e -> e.getName()).collect(Collectors.toList()).contains(item.getName()))
            .collect(Collectors.toList());

     System.out.println(list);
}
@Test
public void test4() {
      //差集newList-oldList基础上   判断 id name 都不相同
      List<StudentDTO> list = newList.stream()
              .filter(item -> !oldList.stream().map(e -> e.getId() + "&" + e.getName())
                      .collect(Collectors.toList()).contains(item.getId() + "&" + item.getName())
              ).collect(Collectors.toList());

     System.out.println(list);
}
@Test
public void test5() {
      //id相同 name不同
      List<StudentDTO> list = newList.stream()
              .filter(item -> oldList.stream().map(e -> e.getId())
                      .collect(Collectors.toList()).contains(item.getId()))
              .filter(item -> !oldList.stream().map(e -> e.getName())
                      .collect(Collectors.toList()).contains(item.getName()))
              .collect(Collectors.toList());

     System.out.println(list);
}