Refactoring

_src/OOP_2020-03-23_3-Universityy/TestApplication.java

@@ -21,10 +21,10 @@ public static void main(String[] args) {
 		Course dep = polito.createCourse("01TXH", "Data Ethics and Protection");
 		polito.printCourses();
 
-		Student alice = polito.createStudent("123456", "Alice");
-		Student bob = polito.createStudent("654321", "Bob");
-		Student carla = polito.createStudent("162534", "Carla");
-		Student david = polito.createStudent("615243", "David");
+		Student alice = polito.addStudent("123456", "Alice");
+		Student bob = polito.addStudent("654321", "Bob");
+		Student carla = polito.addStudent("162534", "Carla");
+		Student david = polito.addStudent("615243", "David");
 		polito.printStudents();
 
 		polito.enroll(oop, alice);

_src/OOP_2020-03-23_3-Universityy/it/polito/oop/university/Course.java

@@ -11,12 +11,10 @@
 
 package it.polito.oop.university;
 
-public class Course {
+public class Course extends StudentsArray {
 	private String code;
 	private String title;
-	private Student[] enrolledStudents = new Student[300];
-	private int numStudents = 0;
-
+
 	Course(String code, String title) {
 		this.code = code;
 		this.title = title;
@@ -33,14 +31,4 @@ public String getCode() {
 	void setTitle(String title) {
 		this.title = title;
 	}
-
-	void addStudent(Student student) {
-		enrolledStudents[numStudents++] = student;
-	}
-
-	public void printStudents() {
-		for (int i = 0; i < numStudents; ++i)
-			System.out.println(i + 1 + ": " + enrolledStudents[i].getName() + 
-					" (" + enrolledStudents[i].getId() + ")");
-	}
 }

_src/OOP_2020-03-23_3-Universityy/it/polito/oop/university/Person.java

@@ -0,0 +1,34 @@
+/*-************************************************************************-*\
+*             *  CLASS SAMPLE FOR "OBJECT ORIENTED PROGRAMMING" (04JEY)      *
+*   #####     *  (!) Mar-2020, Giovanni Squillero <[email protected]>      *
+*  ######     *                                                              *
+*  ###   \    *  Copying and distributing this file, either with or without  *
+*   ##G  c\   *  modification, are permitted in any medium without royalty,  *
+*   #     _\  *  provided that this 10-line comment is preserved.            *
+*   |  _/     *                                                              *
+*             *  ===> THIS FILE IS OFFERED AS-IS, WITHOUT ANY WARRANTY <===  *
+\*-************************************************************************-*/
+
+package it.polito.oop.university;
+
+abstract class Person {
+    private String id;
+    private String name;
+
+    Person(String id, String name) {
+        this.id = id;
+        this.name = name;
+    }
+
+    public String getId() {
+        return id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    void setName(String name) {
+        this.name = name;
+    }
+}

_src/OOP_2020-03-23_3-Universityy/it/polito/oop/university/Professor.java

@@ -11,6 +11,10 @@
 
 package it.polito.oop.university;
 
-public class Professor {
+public class Professor extends Person {
+
+    Professor(String id, String name) {
+        super(id, name);
+    }
 
 }

_src/OOP_2020-03-23_3-Universityy/it/polito/oop/university/Student.java

@@ -11,26 +11,8 @@
 
 package it.polito.oop.university;
 
-public class Student {
-	private String id;
-	private String name;
-
+public class Student extends Person {
 	Student(String id, String name) {
-		this.id = id;
-		this.name = name;
+		super(id, name);
 	}
-
-	public String getId() {
-		return id;
-	}
-
-	public String getName() {
-		return name;
-	}
-
-	void setName(String name) {
-		this.name = name;
-	}
-
-
 }

_src/OOP_2020-03-23_3-Universityy/it/polito/oop/university/StudentsArray.java

@@ -0,0 +1,32 @@
+/*-************************************************************************-*\
+*             *  CLASS SAMPLE FOR "OBJECT ORIENTED PROGRAMMING" (04JEY)      *
+*   #####     *  (!) Mar-2020, Giovanni Squillero <[email protected]>      *
+*  ######     *                                                              *
+*  ###   \    *  Copying and distributing this file, either with or without  *
+*   ##G  c\   *  modification, are permitted in any medium without royalty,  *
+*   #     _\  *  provided that this 10-line comment is preserved.            *
+*   |  _/     *                                                              *
+*             *  ===> THIS FILE IS OFFERED AS-IS, WITHOUT ANY WARRANTY <===  *
+\*-************************************************************************-*/
+
+package it.polito.oop.university;
+
+abstract class StudentsArray {
+	private Student[] enrolledStudents = new Student[300];
+	private int numStudents = 0;
+
+	public void addStudent(Student student) {
+		this.enrolledStudents[this.numStudents++] = student;
+	}
+
+	public Student addStudent(String id, String name) {
+		Student student = new Student(id, name);
+		this.addStudent(student);
+		return student;
+	}
+
+	public void printStudents() {
+		for (int i = 0; i < numStudents; ++i)
+			System.out.println(i + 1 + ": " + enrolledStudents[i].getName() + " (" + enrolledStudents[i].getId() + ")");
+	}
+}

_src/OOP_2020-03-23_3-Universityy/it/polito/oop/university/University.java

@@ -11,41 +11,30 @@
 
 package it.polito.oop.university;
 
-public class University {
+public class University extends StudentsArray {
 	private String name;
 	private Course[] courseArray = new Course[100];
 	private int numCourses = 0; // technically useless (0 is the default)
-	private Student[] studentArray = new Student[100];
-	private int numStudents = 0; // technically useless (0 is the default)
 
 	public University(String name) {
 		this.name = name;
 	}
 
+	public String getName() {
+		return this.name;
+	}
+
 	public Course createCourse(String code, String title) {
 		Course course = new Course(code, title);
 		courseArray[numCourses++] = course;
 		return course;
 	}
 
-	public Student createStudent(String id, String name) {
-		Student student = new Student(id, name);
-		studentArray[numStudents++] = student;
-		return student;
-	}
-
 	public void printCourses() {
 		for (int i = 0; i < numCourses; ++i)
-			System.out.println(i + 1 + ": " + courseArray[i].getTitle() + 
-					" (" + courseArray[i].getCode() + ")");
+			System.out.println(i + 1 + ": " + courseArray[i].getTitle() + " (" + courseArray[i].getCode() + ")");
 	}
 
-	public void printStudents() {
-		for (int i = 0; i < numStudents; ++i)
-			System.out.println(i + 1 + ": " + studentArray[i].getName() + 
-					" (" + studentArray[i].getId() + ")");
-	}
-
 	public void enroll(Course course, Student student) {
 		course.addStudent(student);
 	}