refactoring: adjusting variables names in Administration class

src/main/java/org/example/Administration.java

@@ -207,8 +207,8 @@ public class Administration {
     {
         //Instance variables
 
-        String UserId = null;
-        String UserName = null;
+        String userId = null;
+        String userName = null;
 
         System.out.print("Enter the type of user (1-Student, 2-Admin, 3-Professor): ");
         int userType = scanner.nextInt();
@@ -219,28 +219,28 @@ public class Administration {
         {
             System.out.println("Enter the User Details!");
             System.out.print("Name: ");
-            UserName = scanner.next();
+            userName = scanner.next();
             System.out.print("ID: ");
-            UserId = scanner.next();
+            userId = scanner.next();
 
             //Checks if the entered id is already being used
-            if(findProfessorById(UserId) != null || findAdminById(UserId) != null || findStudentById(UserId) != null)
+            if(findProfessorById(userId) != null || findAdminById(userId) != null || findStudentById(userId) != null)
             {
                 //the entered id is used
                 System.out.println("Please enter an ID which is not being used!");
 
             }
-            else if(findProfessorById(UserId) == null || findAdminById(UserId) == null || findStudentById(UserId) == null)
+            else if(findProfessorById(userId) == null || findAdminById(userId) == null || findStudentById(userId) == null)
             {
                 //the entered id is not used
 
 
-                if(!rightPrefix(UserId, userType))
+                if(!rightPrefix(userId, userType))
                 {
                     //the prefix is wrong
 
                 }
-                else if(!isNumber(UserId))
+                else if(!isNumber(userId))
                 {
                     //the substring does not contain only digits
                     System.out.println("Every character besides the first one need to be digits");
@@ -258,15 +258,15 @@ public class Administration {
             switch (userType)
             {
                 case 1: //Student
-                    Student student = new Student(UserName, UserId, "Student");
+                    Student student = new Student(userName, userId, "Student");
                     addStudents(student);
                     break;
                 case 2: //Admin
-                    Admin admin = new Admin(UserName, UserId, "Admin");
+                    Admin admin = new Admin(userName, userId, "Admin");
                     addAdmin(admin);
                     break;
                 case 3: //Professor
-                    Professor professor = new Professor(UserId, UserName, "Professor");
+                    Professor professor = new Professor(userId, userName, "Professor");
                     addProfessor(professor);
                 default: //Error
                     break;