Question

A. Create a CollegeCourse class. The class contains fields for the course ID (for example, CIS 210), credit hours (for example, 3), and a letter grade (for example, A). Include get and set methods for each field. Create a Student class containing an ID number and an array of five CollegeCourse objects.

Create a get and set method for the Student ID number. Also create a get method that returns one of the Student’s CollegeCourses; the method takes an integer argument and returns the CollegeCourse in that position (0 through 4). Next, create a set method that sets the value of one of the Student’s CollegeCourse objects; the method takes two arguments—a CollegeCourse and an integer representing the CollegeCourse’s position (0 through 4).

B. Write an application that prompts a professor to enter grades for five different courses each for 10 students. Prompt the professor to enter data for one student at a time, including student ID and course data for five courses. Use prompts containing the number of the student whose data is being entered and the course number—for example, Enter ID for student #1, and Enter course ID #5. Verify that the professor enters only A, B, C, D, or F for the grade value for each course. After all the data has been entered, display all the information in order by student then course as shown:

Student #1  ID #101
CS1 1  -- credits. Grade is A
CS2 2  -- credits. Grade is B
CS3 3  -- credits. Grade is C
CS4 4  -- credits. Grade is D
CS5 5  -- credits. Grade is F

CollegeCourse.java

public class CollegeCourse {
private String courseID;
private int credits;
private char grade;
public String getID() {
}
public int getCredits() {
}
public char getGrade() {
}
public void setID(String idNum) {
}
public void setCredits(int cr) {
}
public void setGrade(char gr) {
}
}

InputGrades.java

import java.util.*;
public class InputGrades {
public static void main(String[] args) {
// Write your code here
}
}

Student.java

public class Student {
private int stuID;
private CollegeCourse[] course = new CollegeCourse[5];

public int getID() {
}
public CollegeCourse getCourse(int x) {
}

public void setID(int idNum) {
}
public void setCourse(CollegeCourse c, int x) {
}
}

Answer 1

Here is the completed code for this problem. Comments are included, go through it, learn how things work and let me know if you have any doubts or if you need anything to change. If you are satisfied with the solution, please rate the answer. Thanks

// InputGrades.java

import java.util.*;

public class InputGrades {

      public static void main(String[] args) {

            // scanner for input

            Scanner scanner = new Scanner(System.in);

            // number of courses and students

            int courseCount = 5, studentsCount = 10;

            // creating an array of Student objects

            Student students[] = new Student[studentsCount];

            // looping for studentCount times

            for (int i = 0; i < studentsCount; i++) {

                  // creating a student

                  Student s = new Student();

                  // asking for student id, reading and updating in s

                  System.out.print("Enter student id: ");

                  int studentId = scanner.nextInt();

                  s.setID(studentId);

                  int index = 0;

                  // looping until all course data is entered for current student

                  while (index < courseCount) {

                        // asking for course data. to make things simple and easy to

                        // input, we are reading course id, credits and grade together

                        // (in one line), or it will be difficult to enter 3*5*10 inputs

                        // separately

                        System.out.print("Enter id, credits and grade for course#"

                                    + (index + 1) + ": ");

                        // the input must be in the format <courseId> <credits> <grade>

                        String courseId = scanner.next();

                        int credits = scanner.nextInt();

                        char grade = scanner.next().toUpperCase().charAt(0);

                        // validating the grade

                        if (grade == 'A' || grade == 'B' || grade == 'C'

                                    || grade == 'D' || grade == 'F') {

                              // valid, creating a Course and setting attributes

                              CollegeCourse course = new CollegeCourse();

                              course.setCredits(credits);

                              course.setGrade(grade);

                              course.setID(courseId);

                              // setting course at index position in Student s

                              s.setCourse(course, index);

                              // updating index

                              index++;

                        } else {

                              // invalid grade

                              System.out.println("Invalid grade!");

                        }

                  }

                  // adding s to array at index i

                  students[i] = s;

            }

            // looping and displaying details of all students

            for (int i = 0; i < studentsCount; i++) {

                  System.out.println("\nStudent #" + (i + 1) + " ID #"

                              + students[i].getID());

                  for (int j = 0; j < courseCount; j++) {

                        // since we implemented toString method in CollegeCourse class,

                        // we can simply print it

                        System.out.println(students[i].getCourse(j));

                  }

            }

      }

}

// Student.java

public class Student {

      private int stuID;

      private CollegeCourse[] course = new CollegeCourse[5];

      public int getID() {

            return stuID;

      }

      public CollegeCourse getCourse(int x) {

            return course[x];

      }

      public void setID(int idNum) {

            stuID = idNum;

      }

      public void setCourse(CollegeCourse c, int x) {

            course[x] = c;

      }

     

}

// CollegeCourse.java

public class CollegeCourse {

      private String courseID;

      private int credits;

      private char grade;

      public String getID() {

            return courseID;

      }

      public int getCredits() {

            return credits;

      }

      public char getGrade() {

            return grade;

      }

      public void setID(String idNum) {

            courseID = idNum;

      }

      public void setCredits(int cr) {

            credits = cr;

      }

      public void setGrade(char gr) {

            grade = gr;

      }

      // returns a String containing course id, credits and grade

      public String toString() {

            return courseID + " " + credits + " -- credits. Grade is " + grade;

      }

}

/*sample OUTPUT for 2 courses & 3 students*/

Enter student id: 101

Enter id, credits and grade for course#1: CS1 1 A

Enter id, credits and grade for course#2: CS2 2 X

Invalid grade!

Enter id, credits and grade for course#2: CS2 2 B

Enter student id: 103

Enter id, credits and grade for course#1: CS1 1 C

Enter id, credits and grade for course#2: ENG 2 D

Enter student id: 107

Enter id, credits and grade for course#1: CS2 1 B

Enter id, credits and grade for course#2: CS2 2 C

Student #1 ID #101

CS1 1 -- credits. Grade is A

CS2 2 -- credits. Grade is B

Student #2 ID #103

CS1 1 -- credits. Grade is C

ENG 2 -- credits. Grade is D

Student #3 ID #107

CS2 1 -- credits. Grade is B

CS2 2 -- credits. Grade is C