String nullOption value for the LookupPickerField causes the exception #1132

modules/gui/src/com/haulmont/cuba/gui/components/LookupField.java

@@ -33,9 +33,34 @@ public interface LookupField<V> extends OptionsField<V, V>, HasInputPrompt, Buff
         return new TypeToken<LookupField<T>>() {};
     }
 
+    /**
+     * @deprecated Use {@link #getNullSelectionCaption()} instead
+     */
+    @Deprecated
     V getNullOption();
+
+    /**
+     * @deprecated Use {@link #setNullSelectionCaption(String)} instead
+     */
+    @Deprecated
     void setNullOption(V nullOption);
 
+    /**
+     * @return the null selection caption, not {@code null}
+     */
+    String getNullSelectionCaption();
+
+    /**
+     * Sets the null selection caption.
+     * <p>
+     * The empty string {@code ""} is the default null selection caption.
+     * <p>
+     * If null selection is allowed then the null item will be shown with the given caption.
+     *
+     * @param nullOption the caption to set, not {@code null}
+     */
+    void setNullSelectionCaption(String nullOption);
+
     FilterMode getFilterMode();
     void setFilterMode(FilterMode mode);
 

modules/gui/src/com/haulmont/cuba/gui/xml/layout/loaders/LookupFieldLoader.java

@@ -58,7 +58,7 @@ public class LookupFieldLoader extends AbstractFieldLoader<LookupField> {
 
         String nullName = element.attributeValue("nullName");
         if (StringUtils.isNotEmpty(nullName)) {
-            resultComponent.setNullOption(loadResourceString(nullName));
+            resultComponent.setNullSelectionCaption(loadResourceString(nullName));
         }
 
         String pageLength = element.attributeValue("pageLength");

modules/web-widgets/src/com/haulmont/cuba/web/widgets/CubaComboBoxPickerField.java

@@ -90,6 +90,10 @@ public class CubaComboBoxPickerField<T> extends CubaPickerField<T> {
         getFieldInternal().setItems(captionFilter, items);
     }
 
+    public String getEmptySelectionCaption() {
+        return getFieldInternal().getEmptySelectionCaption();
+    }
+
     public void setEmptySelectionCaption(String caption) {
         getFieldInternal().setEmptySelectionCaption(caption);
     }

modules/web-widgets/src/com/haulmont/cuba/web/widgets/CubaSearchSelectPickerField.java

@@ -92,6 +92,10 @@ public class CubaSearchSelectPickerField<T> extends CubaPickerField<T> {
         getFieldInternal().setItems(captionFilter, items);
     }
 
+    public String getEmptySelectionCaption() {
+        return getFieldInternal().getEmptySelectionCaption();
+    }
+
     public void setEmptySelectionCaption(String caption) {
         getFieldInternal().setEmptySelectionCaption(caption);
     }

modules/web/src/com/haulmont/cuba/web/gui/components/WebLookupField.java

@@ -85,7 +85,7 @@ public class WebLookupField<V> extends WebV8AbstractField<CComboBox<V>, V, V>
         attachValueChangeListener(component);
         setNewOptionAllowed(false);
 
-        component.setItemCaptionGenerator(this::generateDefaultItemCaption);
+        component.setItemCaptionGenerator(this::generateItemCaption);
 
         /* vaadin8 move to new item handler
         component.setNewItemHandler(newItemCaption -> {
@@ -238,8 +238,17 @@ public class WebLookupField<V> extends WebV8AbstractField<CComboBox<V>, V, V>
     @Override
     public void setNullOption(V nullOption) {
         this.nullOption = nullOption;
+        setNullSelectionCaption(generateItemCaption(nullOption));
+    }
 
-        component.setEmptySelectionCaption(generateItemCaption(nullOption));
+    @Override
+    public String getNullSelectionCaption() {
+        return component.getEmptySelectionCaption();
+    }
+
+    @Override
+    public void setNullSelectionCaption(String nullOption) {
+        component.setEmptySelectionCaption(nullOption);
 
         setInputPrompt(null);
     }

modules/web/src/com/haulmont/cuba/web/gui/components/WebLookupPickerField.java

@@ -106,7 +106,7 @@ public class WebLookupPickerField<V extends Entity> extends WebPickerField<V>
     @Override
     protected void initComponent(CubaPickerField<V> component) {
         ((CubaComboBoxPickerField<V>) component)
-                .setItemCaptionGenerator(this::generateDefaultItemCaption);
+                .setItemCaptionGenerator(this::generateItemCaption);
 
         component.addShortcutListener(new ShortcutListenerDelegate("clearShortcut",
                 ShortcutAction.KeyCode.DELETE, new int[]{ShortcutAction.ModifierKey.SHIFT})
@@ -148,8 +148,17 @@ public class WebLookupPickerField<V extends Entity> extends WebPickerField<V>
     @Override
     public void setNullOption(V nullOption) {
         this.nullOption = nullOption;
+        setNullSelectionCaption(generateItemCaption(nullOption));
+    }
 
-        getComponent().setEmptySelectionCaption(generateItemCaption(nullOption));
+    @Override
+    public String getNullSelectionCaption() {
+        return getComponent().getEmptySelectionCaption();
+    }
+
+    @Override
+    public void setNullSelectionCaption(String nullOption) {
+        getComponent().setEmptySelectionCaption(nullOption);
 
         setInputPrompt(null);
     }

modules/web/src/com/haulmont/cuba/web/gui/components/WebSearchPickerField.java

@@ -112,7 +112,7 @@ public class WebSearchPickerField<V extends Entity> extends WebPickerField<V>
         Messages messages = applicationContext.getBean(Messages.NAME, Messages.class);
         setInputPrompt(messages.getMainMessage("searchPickerField.inputPrompt"));
 
-        getComponent().setItemCaptionGenerator(this::generateDefaultItemCaption);
+        getComponent().setItemCaptionGenerator(this::generateItemCaption);
         getComponent().setFilterHandler(this::executeSearch);
     }
 
@@ -258,8 +258,17 @@ public class WebSearchPickerField<V extends Entity> extends WebPickerField<V>
     @Override
     public void setNullOption(V nullOption) {
         this.nullOption = nullOption;
+        setNullSelectionCaption(generateItemCaption(nullOption));
+    }
 
-        getComponent().setEmptySelectionCaption(generateItemCaption(nullOption));
+    @Override
+    public String getNullSelectionCaption() {
+        return getComponent().getEmptySelectionCaption();
+    }
+
+    @Override
+    public void setNullSelectionCaption(String nullOption) {
+        getComponent().setEmptySelectionCaption(nullOption);
 
         setInputPrompt(null);
     }