Files
oop/assignment4/Question5/Course.java
2022-04-21 15:43:38 +08:00

114 lines
2.6 KiB
Java

/*
* Author: CHEN Yongyuan (Walter) 1930006025 from OOP(1007)
* Date: 2022-04-18
* Description: This is the Course class.
*/
public abstract class Course implements Learnable {
/**
* The code of the course.
*/
private String code;
/**
* The title of the course.
*/
private String title;
/**
* The pre-requisite of the course.
*
* A course always has only one pre-requisite course and the pre-requisite
* course cannot be null.
*
* @see Course
*/
private Learnable preRequisite;
/**
* Constructor.
*
* @param code The code of the course.
* @param title The title of the course.
* @param preRequisite The pre-requisite of the course. If the pre-requisite
* course is null, the constructor will print a message of
* "pre-requisite course cannot be null!" and return
* directly.
*/
public Course(String code, String title, Learnable preRequisite) {
if (preRequisite == null) {
System.out.println("pre-requisite course cannot be null!");
return;
}
this.code = code;
this.title = title;
this.preRequisite = preRequisite;
}
/**
* Get the code of the course.
*
* @return The code of the course.
*/
public String getCode() {
return code;
}
/**
* Get the title of the course.
*
* @return The title of the course.
*/
public String getTitle() {
return title;
}
/**
* Get the pre-requisite of the course.
*
* @return The pre-requisite of the course.
*/
public Learnable getPreRequisite() {
return preRequisite;
}
/**
* Indicate whether a course is required or not.
*
* One course could either be a required course or a elective course. Some
* courses are required, while the others are not required.
*
* @return True if the course is required, false if the course is not required.
*/
public abstract boolean isRequired();
/**
* Test.
*/
public static void testCourse() {
Course mr = new Course("CS101", "Intro to Java", null) {
@Override
public boolean isRequired() {
return true;
}
};
System.out.println(mr.getCode() == null);
System.out.println(mr.getTitle() == null);
System.out.println(mr.getPreRequisite() == null);
System.out.println(mr.isRequired() == true);
Course me = new Course("CS102", "Intro to Python", mr) {
@Override
public boolean isRequired() {
return false;
}
};
System.out.println(me.getCode() == "CS102");
System.out.println(me.getTitle() == "Intro to Python");
System.out.println(me.getPreRequisite() == mr);
System.out.println(me.isRequired() == false);
}
}