Course.java

package com.course;

public class Course {
    private String id;
    private String name;
    
    public Course(String id,String name){
        this.id =id;
        this.name = name;
    }
    
    public Course(){
        
    }
    
    public void setId(String id){       
        this.id =id;
    }
    
    public String getId(){
        return id;
    }
    
    public void setName(String pname){
        name = pname;
    }
    
    public String getName(){
        return name;
    }
}

Student.java

package com.student;

public class Student {
    private String id;
    private String name;
    
    public Student(String id,String name){
        this.id = id;
        this.name = name;
    }
    
    public String getId() {
        return id;
    }
    public void setId(String id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
}

SelectCourse.java

package com.manager;

public class SelectCourse {
    private String courseId;
    private String studentId;
    
    public SelectCourse(String courseId,String studentId){
        this.courseId =courseId;
        this.studentId =studentId;
    }
    
    public String getCourseId() {
        return courseId;
    }
    public void setCourseId(String courseId) {
        this.courseId = courseId;
    }
    public String getStudentId() {
        return studentId;
    }
    public void setStudentId(String studentId) {
        this.studentId = studentId;
    }
    
}

Manager.java

package com.manager;

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

import com.course.Course;
import com.student.Student;

public class Manager {
    private static List<SelectCourse> courseList = new ArrayList<>();
    private static  Course[] courseData = new Course[3];
    private static Student[] students = new Student[3];
    
    public static void main(String[] args) {
        init();
        Scanner scanner = new Scanner(System.in);
        System.out.print(">");
        while (scanner.hasNext()) {
            String value = scanner.nextLine();
            if(value.equals("exit")){
                break;
            }
            else if(value.startsWith("add")){
                selCourse(value);
            }
            else if(value.startsWith("query")){
                query();
            }
            else{
                System.out.println(value);
            }
            System.out.print(">");
        }
    }
    
    private static void init(){
        
        courseData[0]= new Course("1"," 语文");
        courseData[1]= new Course("2"," 数学");
        courseData[2]= new Course("3"," 英文");
        
        
        students[0] = new Student("1", "张三");
        students[1] = new Student("2", "李四");
        students[2] = new Student("3", "王五");
    }
    
    private static void selCourse(String value){
        String[] cmds = value.split(" ");
        if(!cmds[0].equals("add")){
            System.out.println("this is invalid add cmd:"+value);
        }
        else if(cmds.length!=3){
            System.out.println("this is invalid add cmd:"+value);
        }
        else{
            SelectCourse obj = new SelectCourse(cmds[1],cmds[2]);
            boolean find =false;
            for(Course item:courseData){
                if(item.getId().equals(cmds[2])){
                    find = true;
                }
            }
            if(!find){
                System.out.println("the course is not exist");
                return;
            }
            
            find =false;
            for(Student item:students){
                if(item.getId().equals(cmds[1])){
                    find = true;
                }
            }
            if(!find){
                System.out.println("the syudent is not exist");
                return;
            }
            
            courseList.add(obj);
        }
    }
    
    private static void query(){
        if(courseList.size()==0){
            System.out.println("no select course");
        }
        else{
            for(SelectCourse item:courseList){
                System.out.println(item.getCourseId()+","+item.getStudentId());
            }
        }
    }
}