Finalizing documentation and simplify admin object handling in AdministrationTest file

src/test/java/org/example/AdministrationTest.java

@@ -61,33 +61,34 @@ class AdministrationTest {
         assertEquals(false, test03);
     }
 
+    /**
+     * Test method for {@link Administration#deleteAdmin(String)}.
+     * Verifies the functionality of deleting an admin from the system.
+     */
     @Test
     void deleteAdmin() {
-        // Create an instance of Administration
-        Administration administration = new Administration();
-
         // Create some sample admins
         Admin admin1 = new Admin("Saul Goodman", "A123456", "Admin");
         Admin admin2 = new Admin("Mike Unknown", "A789012", "Admin");
 
         // Add admins to the administration
-        administration.addAdmin(admin1);
-        administration.addAdmin(admin2);
+        admin.addAdmin(admin1);
+        admin.addAdmin(admin2);
 
         // Attempt to delete an admin (admin1)
-        boolean deleted = administration.deleteAdmin("A123456");
+        boolean deleted = admin.deleteAdmin("A123456");
 
         // Check if the admin is deleted successfully
         assertTrue(deleted);
 
         // Check if the admin is no longer in the system
-        assertNull(administration.findAdminById("A123456"));
+        assertNull(admin.findAdminById("A123456"));
 
         // Check if the other admin (admin2) still exists in the system
-        assertNotNull(administration.findAdminById("A789012"));
+        assertNotNull(admin.findAdminById("A789012"));
 
         // Attempt to delete a non-existing admin
-        boolean nonExistingAdminDeleted = administration.deleteAdmin("A999999");
+        boolean nonExistingAdminDeleted = admin.deleteAdmin("A999999");
 
         // Check if the deletion of non-existing admin returns false
         assertFalse(nonExistingAdminDeleted);
@@ -104,10 +105,12 @@ class AdministrationTest {
         assertEquals(student, student2);
     }
 
+    /**
+     * Test method for {@link Administration#addStudents(Student)}.
+     * Verifies the functionality of adding a student to the system.
+     */
     @Test
     void addStudents() {
-        Administration admin = new Administration();
-
         // Creating a sample student
         Student student = new Student("Walter White", "S123456", "Student");
 
@@ -130,6 +133,10 @@ class AdministrationTest {
         assertEquals("Student", retrievedStudent.getRole());
     }
 
+    /**
+     * Test method for {@link Administration#deleteStudents(String)}.
+     * Verifies the functionality of deleting a student from the system.
+     */
     @Test
     void deleteStudents() {
         Student student1 = new Student("Walter White", "S123456", "Student");