A user adds a record to a table but not shown in B users table when a refre

Hi My code is as follows

I have a notes table and i want to update the table every 2 sceonds so that concurrent users can see the added notes for a specific object.

I have refresher which runs and it doesnt seem to be getting the updates. But when the refresh button is clicked I could see the added notes. 

When User A adds a note, user A can see the added notes in the table. But User B cannot see, he simply has to click refresh to see the new notes added by A.

the code in the addnotespopover is this. 
 VaadinSession.getCurrent().lock();
NoteResponse noteResponse = (NoteResponse) response.getData();
                 Note newNote = (Note) noteResponse.getNote();
                 mainTable.getContainerDataSource().addItem(newNote);
                 mainTable.setSortContainerPropertyId("created");
                 mainTable.sort();
                 mainTable.refreshRowCache();

finally {
                 VaadinSession.getCurrent().unlock();            
            }

This is the method for the refresher
if (VaadinSession.getCurrent().getAttribute(FUser.class) != null) {
            final Refresher refersher = new Refresher();
            refersher.setRefreshInterval(applicationProperties.getNotesRefreshTime());
            refersher.addListener(new RefreshListener() {
                @Override
                public void refresh(Refresher source) {
                    
                    
                    if (noteTable != null) {
                        notesTableLayout.removeComponent(notesPanel);
                        notesTableLayout.removeComponent(addNoteButton);

                        notesTableLayout.addComponent(buildNotesPanel());
                        
                        notesTableLayout.addComponent(addNoteButton);
                    }
                }
            });

            MobileUI.getApp().addExtension(refersher);

Can someone please advise me?

Have you enabled push (@Push annotation on UI class)?

And in your refresh method run code that performs UI changes in UI.access()

refersher.addListener(new RefreshListener() {
   public void refresh(Refresher source) {
      ui.access( new Runnable() {
          public void run() {
            if (noteTable != null) {
               notesTableLayout.removeComponent(notesPanel);
               notesTableLayout.removeComponent(addNoteButton);
               notesTableLayout.addComponent(buildNotesPanel());
               notesTableLayout.addComponent(addNoteButton);
            }
          }
      })
   }
})

By the way, I think you don't need to lock and unlock session when adding note.

Regards
Marco