Qfyilyi

I am trying to load use this query and the values into a map

LinkedHashMap<SCRegionPriority, String> hash = new LinkedHashMap<>();

pstmt=("SELECT a.Id,a.RegionName,ISNULL(b.Priority,0) as priority 

      FROM dbo.region a left join dbo.SCMap b on a.Id = b.RegionId 

      and a.CountryId = b.CountryId and b.SCId=1 where a.CountryId ='1'")

ResultSet rs = pstmt.executeQuery();

con.commit();

    while (rs.next()) {

            SCPri c = new SCPri();

            c.setRegionid(rs.getInt(1));

            c.setRegionname(rs.getString(2));

            c.setPriority(rs.getInt(3));

            hash.put(c, String.valueOf(rs.getInt(3)));

        }

the query gives me the following values:

1,0|2,1|3,1|4,2|...

And then I am trying to load this into the vaadin grid like the following:

     List<HashMap<SCPri, String>> rows = new ArrayList<>();

     LinkedHashMap<SCPri, String> fakeBean1 = subdao1.getSCMap(subcontractor.getId(),subcontractor.getCountryId());

     rows.add(fakeBean1);

     Grid<HashMap<SCPri, String>> grid2 = new Grid<>();

     grid2.setItems(rows);



     for (Map.Entry<SCPri, String> entry : s.entrySet()) {

         grid2.addColumn(h -> h.get(entry.getKey().getRegionname())).setCaption(entry.getKey().getRegionname());

     }

     addComponents(grid2);

I am not able to load the grid with the columns dynamically generated and one editable row of with values underneath those columns.
I am trying to make the grid look like the following:

r1|r2|r3|r4

0 |1 |1 |2

I tried to follow the following two links but failed to get it working:

• How to fill Vaadin Grid with Map items type




• https://vaadin.com/forum/thread/16038356/grid-8-without-bean-class

How can I achieve this?

A single row with empty cells implies that the value provider callback for each cell returns null (or "").

In your case, the value provider callback is h -> h.get(entry.getKey().getRegionname()). Here, h represents the row object, i.e. your single HashMap<SCPri, String> instance. I'm assuming getRegionname() returns something like a String, which would surely cause null results from h.get() since h uses SCPri instances as they key. Changing the callback to h -> h.get(entry.getKey()) instead might do the trick.

It is an unfortunate leftover from the pre-generics times that Map::get accepts any Object without compilation errors instead of requiring you to pass an instance of the actual key type of the map.