implement course registration system

src/CourseRegistrationStarter/Main.java

@@ -4,11 +4,31 @@ public class Main {
     public static void main(String[] args) {
         // TODO:
         // 1. Create at least 3 courses
+        Course course1 = new Course("AP", "AP1404", 30);
+        Course course2 = new Course("python", "python1405", 25);
+        Course course3 = new Course("math", "math1406", 60);
+        Course course4 = new Course("physics", "Ph1404", 15);
         // 2. Create 1 student
+        Student student1 = new Student("emad", "1422");
         // 3. Create a registration system
+        RegistrationSystem Rs = new RegistrationSystem();
         // 4. Add courses to the system
+        Rs.addCourseToSystem(course1);
+        Rs.addCourseToSystem(course2);
+        Rs.addCourseToSystem(course3);
+        Rs.addCourseToSystem(course4);
         // 5. Register the student in some courses
+        student1.addCourse(course1);
+        student1.addCourse(course3);
+        student1.addCourse(course4);
+        student1.addCourse(course1);
         // 6. Drop one course
+        student1.dropCourse(course3);
         // 7. Print the final registered course list
+        student1.showRegisteredCourses();
+        System.out.println();
+        Rs.showAllCourses();
+        System.out.println();
+        Rs.showCoursesCapacity();
     }
 }

src/CourseRegistrationStarter/RegistrationSystem.java

@@ -1,24 +1,64 @@
 package CourseRegistrationStarter;
 import java.util.ArrayList;
 
-public class RegistrationSystem {
+public class RegistrationSystem
+{
     private ArrayList<Course> courses;
 
     public RegistrationSystem() {
         courses = new ArrayList<>();
     }
 
-    public void addCourseToSystem(Course c) {
+    public void addCourseToSystem(Course c)
+    {
         // TODO: Add the course to the system
+        courses.add(c);
     }
 
-    public Course findCourseByCode(String code) {
+    public Course findCourseByCode(String code)
+    {
         // TODO: Search for a course by course code
         // Return the matching course if found, otherwise return null
+        for(Course course: courses)
+        {
+            if(course.getCourseCode().equals(code))
+            {
+                return course;
+            }
+        }
+        return null;
+    }
+    public Course findCourseByName(String name)
+    {
+        // TODO: Search for a course by course code
+        // Return the matching course if found, otherwise return null
+        for(Course course: courses)
+        {
+            if(course.getCourseName().equals(name))
+            {
+                return course;
+            }
+        }
         return null;
     }
 
     public void showAllCourses() {
         // TODO: Print all courses in the system
+        for(Course course: courses)
+        {
+            String name = course.getCourseName();
+            String code = course.getCourseCode();
+            int capacity = course.getCapacity();
+            System.out.printf("%s:\n", name);
+            System.out.printf("    %s: %s\n    %s: %d\n", "code", code, "capacity", capacity);
+        }
+    }
+    public void showCoursesCapacity()
+    {
+        System.out.println("Capacities:");
+        for(Course c: courses)
+        {
+            System.out.printf("    %S: %d", c.getCourseName(), c.getCapacity());
+        }
     }
 }

src/CourseRegistrationStarter/Student.java

@@ -5,7 +5,7 @@ public class Student {
     private String name;
     private String studentId;
     private ArrayList<Course> registeredCourses;
-
+    private int limitation = 5; //you can't get more than 5 courses
     public Student(String name, String studentId) {
         this.name = name;
         this.studentId = studentId;
@@ -20,20 +20,42 @@ public class Student {
         return studentId;
     }
 
-    public boolean addCourse(Course c) {
+    public boolean addCourse(Course c)
+    {
         // TODO: Register the student in the course if capacity allows
         // Return true if registration was successful, otherwise false
+        if(c.getCapacity() > 0 && !registeredCourses.contains(c)
+                && registeredCourses.size() < limitation)
+        {
+            registeredCourses.add(c);
+            c.reduceCapacity();
+            return true;
+        }
         return false;
     }
 
-    public boolean dropCourse(Course c) {
+    public boolean dropCourse(Course c)
+    {
         // TODO: Remove the course from the student's list
         // Restore the course capacity if removal was successful
         // Return true if the course was dropped, otherwise false
+        registeredCourses.remove(c);
+        if (!registeredCourses.contains(c))
+        {
+            c.increaseCapacity();
+            return true;
+        }
         return false;
     }
 
-    public void showRegisteredCourses() {
+    public void showRegisteredCourses()
+    {
         // TODO: Print all registered courses
+        for (Course course : registeredCourses)
+        {
+            String courseName = course.getCourseName();
+            String courseCode = course.getCourseCode();
+            System.out.printf("%s: %s\n", courseName, courseCode);
+        }
     }
 }