SQL Query has no results how do I tell that to a user in my program

Question

I am building a program which checks the roles of users. When a button gets pressed it uses the userID to query the role/group table of our database. If a person is not in the role/group tables then they are a requester. I have the following code, and was wondering why the last else if statement is not working.

When we set a person to be a requester, they are literally removed from the role/group tables. So the resultset should be empty. Right?

ResultSet rs = stmt.executeQuery(getRolesQuery2.toString());
                try
                {
                    boolean empty = true;
                    while (rs.next())
                    {
                        empty = false;
                        userRole = rs.getInt(1);
                        userGroup = rs.getInt(2);
                        System.out.println("The Users Current Role/Group is: " +userRole+ "/" +userGroup);
                        if(userRole == 4 && userGroup == 1)
                        {
                            userRoleLbl.setText("The User Role/Group is: " +userRole+ "/" +userGroup+ " NDS Administrator");
                        }
                        else if(userRole == 1 && userGroup == 3)
                        {
                            userRoleLbl.setText("The User Role/Group is: " +userRole+ "/" +userGroup+ " Privacy Administrator");
                        }
                        else if(userRole == 1 && userGroup == 5)
                        {
                            userRoleLbl.setText("The User Role/Group is: " +userRole+ "/" +userGroup+ " Security Administrator");
                        }
                        else if(userRole == 1 && userGroup == 7)
                        {
                            userRoleLbl.setText("The User Role/Group is: " +userRole+ "/" +userGroup+ " ORD Administrator");
                        }
                        else if(userRole == 1 && userGroup == 9)
                        {
                            userRoleLbl.setText("The User Role/Group is: " +userRole+ "/" +userGroup+ " OEF-OIF Administrator");
                        }
                        else if(userRole == 1 && userGroup == 11)
                        {
                            userRoleLbl.setText("The User Role/Group is: " +userRole+ "/" +userGroup+ " Surgery Administrator");
                        }
                        else if(userRole == 1 && userGroup == 13)
                        {
                            userRoleLbl.setText("The User Role/Group is: " +userRole+ "/" +userGroup+ " Capri Administrator");
                        }
                        else if(userRole == 3 && userGroup == 15)
                        {
                            userRoleLbl.setText("The User Role/Group is: " +userRole+ "/" +userGroup+ " DART Super User");
                        }
                        //TODO: Add some handling for if the role/group is not present which means they are a requester
                        else if(empty)
                        {
                            userRoleLbl.setText("The User is a Requester");
                        }

                    }

empty has been set to false on entry to the while loop and never set again so if(empty) can never be true. — JamesB, May 20 '13 at 21:26
if there are no results, will it enter the while loop at all? — The other other Alan, May 20 '13 at 21:28
I followed the steps from the accepted answer here: http://stackoverflow.com/questions/2938812/how-to-find-out-if-a-java-resultset-obtained-is-empty — DarthOpto, May 20 '13 at 21:30

NullPointerException · Accepted Answer · 2013-05-20T21:31:48.090

3

Because you have

empty = false;

inside your while

You should check this value outside the while so that if your result set is empty it will be true

         try
            {
                boolean empty = true;
                while (rs.next())
                {  
                  //your if else
                }

           if(empty)
              {
                userRoleLbl.setText("The User is a Requester");
              }
           }

edited May 20 '13 at 21:31

answered May 20 '13 at 21:26

NullPointerException

3,732
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Removing the `empty = false;` still yields nothing. – DarthOpto May 20 '13 at 21:29
you have to put that check outside the while because if your result set is empty it will not go inside the while loop – NullPointerException May 20 '13 at 21:30

score 0 · Answer 2 · answered May 20 '13 at 21:27

0

If the ResultSet has no results, it will not enter the while() loop at all. You should check for no results, before entering the loop.

answered May 20 '13 at 21:27

The other other Alan

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score 0 · Answer 3 · answered May 20 '13 at 21:34

0

In your code empty is always false, so it will never enter the last if. Maybe you meant to keep the empty = true.

answered May 20 '13 at 21:34

docDevil

72
4

SQL Query has no results how do I tell that to a user in my program

3 Answers3