UC.06 – Subject enrollment
   Context of Use
Student enrolls to one of the so far not enrolled subjects
   
 
   Stakeholders and Interests
   
      - student: intends to enroll in a subject
      
 
   
   
 
   Constraints
   
      - Student cannot enroll in any subject which is not taught yet
 
      - Student cannot enroll in more than 7 subjects
 
   
   
 
   Preconditions
   
      - Student is logged in to the UIS
 
      - Student is on the page Other Subjects
 
   
   
 
   Trigger
Student clicks on the 
Enroll button from the row of the subject intended for enrollment
   
 
   Main Success Scenario
   
      - Student clicks on the Enroll button from the row of the subject intended for enrollment
 
      - UIS system will add the selected subject on the student's list of enrolled subjects
 
      - Message confirming a successful execution will appear
 
   
   
 
   Postconditions
   
      - UIS system will add the selected subject on the student's list of enrolled subjects and will change the tables of the DB accordingly
 
      - Student is still on the page Other Subjects
 
      - Message confirming a successful execution will appear
 
      - The subject will be removed from the table under the menu Other Subjects
 
      - The subject will be added to the list on the table Enrolled Subjects under the menu My Subjects
 
      - The subject will be added to the table under the menu Other Exam Dates
 
      - Teacher's View: the student will appear on the teacher's list of students enrolled in the selected subject from
         the table located on the menu My Subjects
      
 
   
   
 
   Alternative Flows
   
      - 1a.
            Table has no values in it, i.e. the student is already enrolled in all of the existing subjects
         
            - 1a-1.
                  The UC.06 cannot proceed
            
 
         
         
       
      - 1b.
            Button Enroll is disabled for selected subject because the subject has no assigned teacher
         
            - 1b-1.
                  The UC.06 cannot proceed
            
 
         
         
       
      - 1c.
            Button Enroll is disabled for the selected subject, because student has already reached limit of assigned subjects
         
            - 1c-1.
                  The UC.06 cannot proceed
            
 
         
         
       
      - 2a.
            Internal error occurs in the UIS/DB during the subject's registration in the DB
         
            Postconditions:
                  - Student is still on the page Other Subjects
 
                  - Message claiming an unsuccessful execution appears
 
                  - No data are overwritten or changed
 
               
             
         
         
       
   
   
 
   Technology and Data Variations List
N/A
   
 
   Related Information
   
      - All the enroll-able subjects are announced