#13816 fix rows number if selection is empty (#15767)

* #13816 fix rows number if selection is empty

* #13816 add suggestions from code review

* #13816 add comments about code changes

plugins/org.jkiss.dbeaver.ui.editors.data/src/org/jkiss/dbeaver/ui/controls/resultset/ResultSetStatListener.java

@@ -23,8 +23,12 @@ import org.eclipse.jface.viewers.SelectionChangedEvent;
 import org.eclipse.ui.IEditorSite;
 import org.eclipse.ui.IWorkbenchPartSite;
 import org.eclipse.ui.progress.UIJob;
+import org.jkiss.code.NotNull;
+import org.jkiss.code.Nullable;
 import org.jkiss.dbeaver.model.preferences.DBPPreferenceStore;
 
+import java.util.StringJoiner;
+
 class ResultSetStatListener extends ResultSetListenerAdapter {
     private final ResultSetViewer viewer;
     private SLUpdateJob updateJob;
@@ -57,24 +61,32 @@ class ResultSetStatListener extends ResultSetListenerAdapter {
         @Override
         public IStatus runInUIThread(IProgressMonitor monitor) {
             IResultSetSelection selection = viewer.getSelection();
-            if (selection instanceof IResultSetSelectionExt) {
+            DBPPreferenceStore preferenceStore = viewer.getPreferenceStore();
+            updateSelectionStatistics(selection, preferenceStore);
+            return Status.OK_STATUS;
+        }
+
+        private void updateSelectionStatistics(IResultSetSelection selection, DBPPreferenceStore preferenceStore) {
+            if (selection.getSelectedAttributes().isEmpty()) {
+                updateSelectionStatistics(preferenceStore, null);
+            } else if (selection instanceof IResultSetSelectionExt) {
                 IResultSetSelectionExt selectionExt = (IResultSetSelectionExt) selection;
-                DBPPreferenceStore preferenceStore = viewer.getPreferenceStore();
-                String slText = "";
-                if (preferenceStore.getBoolean(ResultSetPreferences.RESULT_SET_SHOW_SEL_ROWS)) {
-                    slText = "Rows: " + selectionExt.getSelectedRowCount();// + "/" + selExt.getSelectedColumnCount() + "/" + selExt.getSelectedCellCount();
-                }
-                if (preferenceStore.getBoolean(ResultSetPreferences.RESULT_SET_SHOW_SEL_COLUMNS)) {
-                    if (!slText.isEmpty()) slText += ", ";
-                    slText += "Cols: " + selectionExt.getSelectedColumnCount();
-                }
-                if (preferenceStore.getBoolean(ResultSetPreferences.RESULT_SET_SHOW_SEL_CELLS)) {
-                    if (!slText.isEmpty()) slText += ", ";
-                    slText += "Cells: " + selectionExt.getSelectedCellCount();
-                }
-                viewer.setSelectionStatistics(slText);
+                updateSelectionStatistics(preferenceStore, selectionExt);
             }
-            return Status.OK_STATUS;
+        }
+
+        private void updateSelectionStatistics(@NotNull DBPPreferenceStore preferenceStore, @Nullable IResultSetSelectionExt selectionExt) {
+            StringJoiner slText = new StringJoiner(", ");
+            if (preferenceStore.getBoolean(ResultSetPreferences.RESULT_SET_SHOW_SEL_ROWS)) {
+                slText.add("Rows: " + (selectionExt == null ? 0 : selectionExt.getSelectedRowCount())) ;// + "/" + selExt.getSelectedColumnCount() + "/" + selExt.getSelectedCellCount();
+            }
+            if (preferenceStore.getBoolean(ResultSetPreferences.RESULT_SET_SHOW_SEL_COLUMNS)) {
+                slText.add("Cols: " + (selectionExt == null ? 0 : selectionExt.getSelectedColumnCount()));
+            }
+            if (preferenceStore.getBoolean(ResultSetPreferences.RESULT_SET_SHOW_SEL_CELLS)) {
+                slText.add("Cells: " + (selectionExt == null ? 0 : selectionExt.getSelectedCellCount()));
+            }
+            viewer.setSelectionStatistics(slText.toString());
         }
     }
 

plugins/org.jkiss.dbeaver.ui.editors.data/src/org/jkiss/dbeaver/ui/controls/resultset/ResultSetViewer.java

@@ -4929,11 +4929,16 @@ public class ResultSetViewer extends Viewer
                             // Restore original position
                             restorePresentationState(presentationState);
                         }
-                        if (focusRow >= 0 && focusRow < model.getRowCount() && model.getVisibleAttributeCount() > 0) {
-                            if (getCurrentRow() == null) {
+                        /*
+                        We allow zero length row list for the situations when we load new an empty resultSet and the last resultSet
+                        wasn't empty. Previously we didn't update the selected row count which caused a problem described in #15767
+                        Now we call the ResultSetStatListener even if the resultSet is empty.
+                         */
+                        if (focusRow >= 0 && (focusRow < model.getRowCount() || model.getRowCount() == 0) && model.getVisibleAttributeCount() > 0) {
+                            if (getCurrentRow() == null && model.getRowCount() > 0) {
                                 setCurrentRow(getModel().getRow(focusRow));
                             }
-                            if (getActivePresentation().getCurrentAttribute() == null) {
+                            if (getActivePresentation().getCurrentAttribute() == null || model.getRowCount() == 0) {
                                 getActivePresentation().setCurrentAttribute(model.getVisibleAttribute(0));
                                 panelUpdated = true; // Attribute viewer refreshed
                             }

plugins/org.jkiss.dbeaver.ui.editors.data/src/org/jkiss/dbeaver/ui/controls/resultset/spreadsheet/SpreadsheetPresentation.java

@@ -346,9 +346,6 @@ public class SpreadsheetPresentation extends AbstractPresentation implements IRe
         this.curAttribute = attribute;
 
         ResultSetRow curRow = controller.getCurrentRow();
-        if (curRow == null) {
-            return;
-        }
         GridCell cell = controller.isRecordMode() ?
             new GridCell(curRow, this.curAttribute) :
             new GridCell(this.curAttribute, curRow);