diff --git a/platform/util/src/com/intellij/util/ui/tree/WideSelectionTreeUI.java b/platform/util/src/com/intellij/util/ui/tree/WideSelectionTreeUI.java
index 8fafbf139b12..05693bdfb267 100644
--- a/platform/util/src/com/intellij/util/ui/tree/WideSelectionTreeUI.java
+++ b/platform/util/src/com/intellij/util/ui/tree/WideSelectionTreeUI.java
@@ -72,7 +72,6 @@ public class WideSelectionTreeUI extends BasicTreeUI {
     boolean handled = false;
     public void mousePressed(@NotNull final MouseEvent e) {
       handled = false;
-      if (!(e.getSource() instanceof JTree)) return;
       if (!isSelected(e)) {
         handled = true;
         handle(e);
@@ -81,7 +80,6 @@ public class WideSelectionTreeUI extends BasicTreeUI {
 
     @Override
     public void mouseReleased(@NotNull final MouseEvent e) {
-      if (!(e.getSource() instanceof JTree)) return;
       if (!handled) {
         handle(e);
       }
@@ -90,9 +88,12 @@ public class WideSelectionTreeUI extends BasicTreeUI {
     private boolean isSelected(MouseEvent e) {
       final JTree tree = (JTree)e.getSource();
       final int selected = tree.getClosestRowForLocation(e.getX(), e.getY());
-      for (int row : tree.getSelectionRows()) {
-        if (row == selected) {
-          return true;
+      final int[] rows = tree.getSelectionRows();
+      if (rows != null) {
+        for (int row : rows) {
+          if (row == selected) {
+            return true;
+          }
         }
       }