first

.idea/encodings.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="Encoding" addBOMForNewFiles="with NO BOM" />
+</project>
\ No newline at end of file

.idea/misc.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_11" default="true" project-jdk-name="11" project-jdk-type="JavaSDK">
+    <output url="file://$PROJECT_DIR$/out" />
+  </component>
+</project>
\ No newline at end of file

.idea/modules.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectModuleManager">
+    <modules>
+      <module fileurl="file://$PROJECT_DIR$/lab9.iml" filepath="$PROJECT_DIR$/lab9.iml" />
+    </modules>
+  </component>
+</project>
\ No newline at end of file

.idea/vcs.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="" vcs="Git" />
+  </component>
+</project>
\ No newline at end of file

lab9.iml

+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>
\ No newline at end of file

src/org/university/core/Course.java

+package org.university.core;
+
+import java.util.ArrayList;
+
+public class Course {
+    private String name;
+    private Professor instructor;
+    private ArrayList<Student> students = new ArrayList<Student>();
+    private GraduateStudent teacherAssistance;
+
+
+    public GraduateStudent getTeacherAssistance() {
+        return teacherAssistance;
+    }
+
+    public void setTeacherAssistance(GraduateStudent teacherAssistance) {
+        this.teacherAssistance = teacherAssistance;
+    }
+
+    public Course(String name, Professor instructor) {
+        this.name = name;
+        this.instructor = instructor;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public Professor getInstructor() {
+        return instructor;
+    }
+
+    public ArrayList<Student> getStudents() {
+        return students;
+    }
+
+    public void addStudent(Student student){
+        this.students.add(student);
+    }
+}

src/org/university/core/Department.java

+package org.university.core;
+
+import java.util.ArrayList;
+
+public class Department {
+    private String name;
+    private ArrayList<Course> courses = new ArrayList<>();
+    public Department(String name){
+        this.name = name;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public ArrayList<Course> getCourses() {
+        return courses;
+    }
+
+    public void addCourse(Course course){
+        courses.add(course);
+    }
+}

src/org/university/core/Person.java

+package org.university.core;
+
+public class Person {
+    protected String firstName;
+    protected String lastName;
+    protected String ID;
+    protected int joiningYear;
+    protected Department department;
+    public Person(String firstName,String lastName,String ID,int joiningYear,Department department){
+        this.firstName=firstName;
+        this.lastName=lastName;
+        this.ID=ID;
+        this.joiningYear=joiningYear;
+        this.department=department;
+    }
+
+    public String getFirstName() {
+        return firstName;
+    }
+
+    public String getLastName() {
+        return lastName;
+    }
+
+    public String getID() {
+        return ID;
+    }
+
+    public int getJoiningYear() {
+        return joiningYear;
+    }
+
+    public Department getDepartment() {
+        return department;
+    }
+}