Modeler cleanup

* entity-appropriate actions

Author: andrus

modeler/cayenne-modeler/src/main/java/org/apache/cayenne/modeler/editor/ObjEntityTabbedView.java

@@ -95,8 +95,11 @@ private void resetRemoveButtons() {
 
     private void currentObjEntityChanged(EntityDisplayEvent e) {
         Entity<?, ?, ?> entity = e.getEntity();
+        if (!(entity instanceof ObjEntity)) {
+            return;
+        }
 
-        if (e.isMainTabFocus() && entity instanceof ObjEntity) {
+        if (e.isMainTabFocus()) {
             if (getSelectedComponent() != entityPanel) {
                 setSelectedComponent(entityPanel);
                 entityPanel.setVisible(true);

modeler/cayenne-modeler/src/main/java/org/apache/cayenne/modeler/editor/dbentity/DbEntityTabbedView.java

@@ -74,9 +74,12 @@ private void stateChanged(ChangeEvent e) {
     }
 
     private void currentDbEntityChanged(EntityDisplayEvent e) {
-        Entity entity = e.getEntity();
+        Entity<?, ?, ?> entity = e.getEntity();
+        if (!(entity instanceof DbEntity)) {
+            return;
+        }
 
-        if (e.isMainTabFocus() && entity instanceof DbEntity) {
+        if (e.isMainTabFocus()) {
             if (getSelectedComponent() != entityPanel) {
                 setSelectedComponent(entityPanel);
                 entityPanel.setVisible(true);