need help building a =hiearchical= JSON object

[Stuart Rogers]

Greetings all,

I've got a servlet with a query that builds a resultset sorted on three fields
-year-program-course-

I'd like to use the org.json classes to build up a hiearchical JSON object that, when used as a datastore for a Dojo Tree widget, makes a pretty Tree. You can see
some examples where I've hard-coded the JSON objects on this page:

http://edawizardry.com/testtree_2.jsp

I'm having some trouble setting/resetting the JSON objects within my while-loop.

What I've got so far...

           Integer prev_fiscal_year;
           Long prev_cte_program_id;
           prev_fiscal_year = 0;
           prev_cte_program_id = 0L;

           //display the output
           if( rs != null) {
               JSONObject data     = new JSONObject();
               JSONArray  years    = new JSONArray();
               rs.next();   // position on first row to preset the toggles
               prev_fiscal_year = rs.getInt("fiscal_year");
               prev_cte_program_id = rs.getLong("vdms_cte_program_id");
               rs.beforeFirst(); //reposition
               while( rs.next()) {
                   if( prev_fiscal_year != rs.getInt("fiscal_year")) {
                       JSONObject year     = new JSONObject();
                       JSONArray programs  = new JSONArray();
                       JSONArray  courses  = new JSONArray();
                       year.put("vdms_idno", Integer.toString( rs.getInt("fiscal_year")));
                       tmpstr = Integer.toString( rs.getInt("fiscal_year"));
                       year.put("cte_name", tmpstr);
                       years.put( year);
                       prev_fiscal_year = rs.getInt("fiscal_year");
                   }
                   if( prev_cte_program_id != rs.getLong("vdms_cte_program_id")) {
                       JSONObject program  = new JSONObject();
                       JSONArray  courses  = new JSONArray();
                       program.put("vdms_idno", Long.toString( rs.getLong("vdms_cte_program_id")));
                       tmpstr = rs.getString("cte_program_id") + " - " + rs.getString("cte_program_name");
                       program.put("line", courses);
                       programs.put( program);
                       prev_cte_program_id = rs.getLong("vdms_cte_program_id");
                   }
                   JSONObject course   = new JSONObject();
                   course.put("vdms_idno", Long.toString( rs.getLong("vdms_cte_course_id")));
                   tmpstr = rs.getString("cte_course_id") + " - " + rs.getString("cte_course_name");
                   course.put("cte_name", tmpstr);
                   courses.put( course);
               }
               data.put("identifier","vdms_idno");
               data.put("label","cte_name");
               data.put("items", years);
               out.println( data.toString() );
           } else {
               System.out.println("no rows returned");
           }

Surely somewhere in the space-time continuum someone has done this kind of thing before?

As always, all comments/suggestions/constructive criticism/and especially examples are always appreciated.

TIA,

Still-learning Stuart

[Stuart Rogers]

Ooops, make that

http://edawizardry.com/testtree_2.jsp

[David Newton]

Those appear to be the same link.

It's not clear what the issue is: what is happening that shouldn't be, or vice-versa?

[Stuart Rogers]

> It's not clear what the issue is: what is happening that shouldn't be, or vice-versa?

Six hours later I'm not sure this could ever be made to work - JSONObject inherits java.util.HashMap and a consequence of this is
a JSONObject is an UNORDERED set of name-value pairs. But for the hiearchical JSON object to be usable as a Dojo datastore it
must have certain name-value pairs appear in a specific order.

So unless someone has a neat trick up their sleeve it's back to string-building -- yuck.


Now what?


Still-stumped Stuart