效果
乱序
[
Student{userName='张三', userNick='2', age=22, createTime='2022-12-02 2:11:00'},
Student{userName='李四', userNick='1', age=23, createTime='2022-12-03 16:11:00'},
Student{userName='王五', userNick='4', age=24, createTime='2022-12-01 21:11:00'},
Student{userName='赵六', userNick='3', age=25, createTime='2022-12-02 22:11:00'}]
升序
[
Student{userName='王五', userNick='4', age=24, createTime='2022-12-01 21:11:00'},
Student{userName='赵六', userNick='3', age=25, createTime='2022-12-02 22:11:00'},
Student{userName='张三', userNick='2', age=22, createTime='2022-12-02 2:11:00'},
Student{userName='李四', userNick='1', age=23, createTime='2022-12-03 16:11:00'}]
降序[
Student{userName='李四', userNick='1', age=23, createTime='2022-12-03 16:11:00'},
Student{userName='张三', userNick='2', age=22, createTime='2022-12-02 2:11:00'},
Student{userName='赵六', userNick='3', age=25, createTime='2022-12-02 22:11:00'},
Student{userName='王五', userNick='4', age=24, createTime='2022-12-01 21:11:00'}]
代码实现
public class Test {
public static void main(String[] args) throws IOException {
//测试数据,请不要纠结数据的严谨性
List<Student> studentList = new ArrayList<>();
studentList.add(new Student("张三","2",22,"2022-12-02 2:11:00"));
studentList.add(new Student("李四","1",23,"2022-12-03 16:11:00"));
studentList.add(new Student("王五","4",24,"2022-12-01 21:11:00"));
studentList.add(new Student("赵六","3",25,"2022-12-02 22:11:00"));
//根据日期进行升序排序
//乱序
System.out.println("乱序"+studentList);
//根据日期进行升序排序
List<Student> studentsSortAsce = studentList.stream().sorted(Comparator.comparing(Student::getCreateTime)).collect(Collectors.toList());
//根据日期进行降序排序
List<Student> studentsSortDesc = studentList.stream().sorted(Comparator.comparing(Student::getCreateTime).reversed()).collect(Collectors.toList());
//升序后输出
System.out.println("升序"+studentsSortAsce);
//降序后输出
System.out.println("降序"+studentsSortDesc);
}
}
class Student{
private String userName;
private String userNick;
private int age;
private String createTime;
public Student() {
}
public Student(String userName, String userNick, int age, String createTime) {
this.userName = userName;
this.userNick = userNick;
this.age = age;
this.createTime = createTime;
}
@Override
public String toString() {
return "Student{" +
"userName='" + userName + ''' +
", userNick='" + userNick + ''' +
", age=" + age +
", createTime='" + createTime + ''' +
'}';
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getUserNick() {
return userNick;
}
public void setUserNick(String userNick) {
this.userNick = userNick;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public String getCreateTime() {
return createTime;
}
public void setCreateTime(String createTime) {
this.createTime = createTime;
}
}
reversed() 进行一个反转的操作
Student::此处填写要排序的字段