add course registration starter code

src/CourseRegistrationStarter/Course.java

@@ -0,0 +1,37 @@
+package CourseRegistrationStarter;
+
+public class Course {
+    private String courseName;
+    private String courseCode;
+    private int capacity;
+
+    public Course(String courseName, String courseCode, int capacity) {
+        this.courseName = courseName;
+        this.courseCode = courseCode;
+        this.capacity = capacity;
+    }
+
+    public String getCourseName() {
+        return courseName;
+    }
+
+    public String getCourseCode() {
+        return courseCode;
+    }
+
+    public int getCapacity() {
+        return capacity;
+    }
+
+    public boolean reduceCapacity() {
+        if (capacity > 0) {
+            capacity--;
+            return true;
+        }
+        return false;
+    }
+
+    public void increaseCapacity() {
+        capacity++;
+    }
+}