finishing TODO parts

src/CourseRegistrationStarter/Main.java

@@ -2,6 +2,27 @@ package CourseRegistrationStarter;
 
 public class Main {
     public static void main(String[] args) {
+        Course BP = new Course("Basic Programing", "1000", 5);
+        Course AP = new Course("Advanced Programing", "1001", 5);
+        Course M = new Course("Math", "1002", 5);
+
+        Student shayan = new Student("Shayan", "404212345");
+
+        RegistrationSystem regSys = new RegistrationSystem();
+        regSys.addCourseToSystem(AP);
+        regSys.addCourseToSystem(BP);
+        regSys.addCourseToSystem(M);
+
+        shayan.addCourse(BP);
+        shayan.addCourse(AP);
+        shayan.addCourse(M);
+
+        shayan.dropCourse(M);
+
+        shayan.showRegisteredCourses();
+
+
+
         // TODO:
         // 1. Create at least 3 courses
         // 2. Create 1 student

src/CourseRegistrationStarter/RegistrationSystem.java

@@ -9,10 +9,15 @@ public class RegistrationSystem {
     }
 
     public void addCourseToSystem(Course c) {
+        courses.add(c);
         // TODO: Add the course to the system
     }
 
     public Course findCourseByCode(String code) {
+        for(int i = 0; i < courses.size(); i++){
+            if (courses.get(i).getCourseCode().equals(code))
+                return courses.get(i);
+        }
         // TODO: Search for a course by course code
         // Return the matching course if found, otherwise return null
         return null;

src/CourseRegistrationStarter/Student.java

@@ -21,12 +21,26 @@ public class Student {
     }
 
     public boolean addCourse(Course c) {
+        if(registeredCourses.contains(c))
+            return false;
+        if((c.getCapacity() > 0)){
+            this.registeredCourses.add(c);
+            c.reduceCapacity();
+            return true;
+        }
         // TODO: Register the student in the course if capacity allows
         // Return true if registration was successful, otherwise false
         return false;
     }
 
     public boolean dropCourse(Course c) {
+        for(int i = 0; i < this.registeredCourses.size(); i++){
+            if (this.registeredCourses.get(i) == c){
+                this.registeredCourses.remove(c);
+                c.increaseCapacity();
+                return true;
+            }
+        }
         // 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
@@ -34,6 +48,9 @@ public class Student {
     }
 
     public void showRegisteredCourses() {
+        for(int i = 0; i < registeredCourses.size(); i++){
+            System.out.println(this.registeredCourses.get(i).getCourseName() + ", code: " + this.registeredCourses.get(i).getCourseCode());
+        }
         // TODO: Print all registered courses
     }
 }