public class CourseIndex {

private String index; //TO do this will be another class

private String courseCode;

private int vacancy;

private int totalSize;

private ArrayList registerIDs = new ArrayList( );

private ArrayList waitIDs = new ArrayList();

private ArrayList classList = new ArrayList();

public CourseIndex() {}

public CourseIndex(int vacancy) {

this.vacancy = vacancy;

}

public CourseIndex(String index, String courseCode, int vacancy, int totalSize, ArrayList registerIDs,

ArrayList waitIDs, ArrayList classList) {

// TODO: check if vacancy > totalSize. If yes, throw and error.

super();

this.index = index;

this.courseCode = courseCode;

this.vacancy = vacancy;

this.totalSize = totalSize;

this.registerIDs = registerIDs;

this.waitIDs = waitIDs;

this.classList = classList;

}

/*

* getter and setter

*/

public ArrayList getClassList() {

return classList;

}

public void setClassList(ArrayList classList) {

this.classList = classList;

}

public ArrayList getRegisterIDs() {

return registerIDs;

}

public ArrayList getWaitIDs() {

return waitIDs;

}

public void setWaitIDs(ArrayList waitIDs) {

this.waitIDs = waitIDs;

}

public String getIndex() {

return index;

}

public void setIndex(String index) {

this.index = index;

}

public String getCourseCode() {

return courseCode;

}

public void setCourseCode(String courseCode) {

this.courseCode = courseCode;

}

public int getVacancy() {

return vacancy;

}

public void setVacancy(int vacancy) {

this.vacancy = vacancy;

}

public ArrayList getRegisteredIDs() {

return registerIDs;

}

public void setRegisterIDs(ArrayList RegisterIDs) {

this.registerIDs = RegisterIDs;

}

/*

* add and remove student to this index

*/

public int addStudent(String studentID) {

if(studentID != null) {

int main_std_i = this.registerIDs.indexOf(studentID);

int wait_std_i = this.waitIDs.indexOf(studentID);

if(main_std_i >= 0 || wait_std_i >= 0) { // student already registered for this course yet

System.out.println("Student " + studentID + " already registered!");

return -1;

}

if(this.vacancy > 0) {

registerIDs.add(studentID);

this.vacancy-- ;

System.out.println("Vancancy = " + this.vacancy);

return 1;

} else {

waitIDs.add(studentID);

System.out.println("Student added to waitlist. Vacancy exceeded");

return 0;

}

}

return -1;

}

public int removeStudent(String studentID) {

int main_std_i = this.registerIDs.indexOf(studentID);

int wait_std_i = this.waitIDs.indexOf(studentID);

if(main_std_i < 0 && wait_std_i < 0) {

return -1; // students not registered for this course

} else if(main_std_i < 0 && wait_std_i >= 0) {

waitIDs.remove(wait_std_i);

return 0;

} else {

registerIDs.remove(main_std_i);

this.vacancy ++;

return 1;

}

}

public static void main(String[] args) {

CourseIndex courseIndex = new CourseIndex(1);

courseIndex.addStudent("std001");

courseIndex.addStudent("std002");

System.out.println(courseIndex.getRegisteredIDs());

courseIndex.removeStudent("std003");

System.out.println(courseIndex.getRegisteredIDs());

courseIndex.removeStudent("std002");

System.out.println(courseIndex.getRegisteredIDs());

}

public int getTotalSize() {

return totalSize;

}

public void setTotalSize(int totalSize) {

this.totalSize = totalSize;

}

}

Draw a technical UML sequence diagram using visual paradigm software with the code above.