Java で簡単な学生の宿題提出期限リマインダー システムを実装するにはどうすればよいですか?

public class Student {
    private String name;
    private String ID;
    
    public Student(String name, String ID) {
        this.name = name;
        this.ID = ID;
    }
    
    // getter and setter methods
    
    // 提醒学生提交作业的方法
    public void remindToSubmitAssignment(Assignment assignment) {
        System.out.println("Dear " + name + ", please submit your assignment before " + assignment.getDeadline() + ".");
    }
}

public class Assignment {
    private String name;
    private String deadline;

    public Assignment(String name, String deadline) {
        this.name = name;
        this.deadline = deadline;
    }

    // getter and setter methods
    
    public String getDeadline() {
        return deadline;
    }
}

public class Main {
    public static void main(String[] args) {
        Student student = new Student("张三", "123456");
        Assignment assignment = new Assignment("数学作业", "2021年10月10日 23:59");
        
        student.remindToSubmitAssignment(assignment);
    }
}