Bug-653: Fixed NullPointerException for com.magento.idea.magento2plugin.actions.generation.InjectAViewModelAction#getElement

Author: bohdan-harniuk

src/com/magento/idea/magento2plugin/actions/generation/InjectAViewModelAction.java

@@ -22,78 +22,110 @@
 import org.jetbrains.annotations.NotNull;
 
 public class InjectAViewModelAction extends DumbAwareAction {
-    public static String actionName = "Inject a new View Model for this block";
-    public static String actionDescription = "Inject a new Magento 2 View Model";
+
+    public static final String ACTION_NAME = "Inject a new View Model for this block";
+    public static final String ACTION_DESCRIPTION = "Inject a new Magento 2 View Model";
     private XmlTag targetXmlTag;
 
+    /**
+     * An action constructor.
+     */
     public InjectAViewModelAction() {
-        super(actionName, actionDescription, MagentoIcons.MODULE);
+        super(ACTION_NAME, ACTION_DESCRIPTION, MagentoIcons.MODULE);
     }
 
     @Override
-    public void update(final AnActionEvent event) {
+    public void update(final @NotNull AnActionEvent event) {
+        this.setStatus(event, false);
         final Project project = event.getData(PlatformDataKeys.PROJECT);
+
+        if (project == null) {
+            return;
+        }
+
         if (Settings.isEnabled(project)) {
             final XmlTag element = getElement(event);
-            if (element == null) {
-                this.setStatus(event, false);
-            } else  {
+
+            if (element != null) {
                 targetXmlTag = element;
                 this.setStatus(event, true);
             }
-        } else {
-            this.setStatus(event, false);
         }
     }
 
-    private void setStatus(final AnActionEvent event, final boolean status) {
-        event.getPresentation().setVisible(status);
-        event.getPresentation().setEnabled(status);
-    }
-
     @Override
     public void actionPerformed(final @NotNull AnActionEvent event) {
-        InjectAViewModelDialog.open(event.getProject(), this.targetXmlTag);
+        final Project project = event.getData(PlatformDataKeys.PROJECT);
+
+        if (project == null || targetXmlTag == null) {
+            return;
+        }
+        InjectAViewModelDialog.open(project, targetXmlTag);
     }
 
     @Override
     public boolean isDumbAware() {
         return false;
     }
 
+    /**
+     * Get focused (target) element for the event.
+     *
+     * @param event AnActionEvent
+     *
+     * @return XmlTag
+     */
     private XmlTag getElement(final @NotNull AnActionEvent event) {
         final Caret caret = event.getData(PlatformDataKeys.CARET);
+
         if (caret == null) {
             return null;
         }
 
-        final int offset = caret.getOffset();
         final PsiFile psiFile = event.getData(PlatformDataKeys.PSI_FILE);
+
+        if (psiFile == null) {
+            return null;
+        }
+        final int offset = caret.getOffset();
         final PsiElement element = psiFile.findElementAt(offset);
+
         if (element == null) {
             return null;
         }
-
         final XmlTag xmlTag = PsiTreeUtil.getParentOfType(element, XmlTag.class);
 
         if (xmlTag == null) {
             return null;
         }
         XmlTag resultTag;
-        if (xmlTag.getName().equals(CommonXml.ATTRIBUTE_ARGUMENTS)) {
+
+        if (CommonXml.ATTRIBUTE_ARGUMENTS.equals(xmlTag.getName())) {
             resultTag = PsiTreeUtil.getParentOfType(xmlTag, XmlTag.class);
         } else {
             resultTag = xmlTag;
         }
+
         if (resultTag == null) {
             return null;
         }
 
-        if (!resultTag.getName().equals(LayoutXml.BLOCK_ATTRIBUTE_TAG_NAME)
-                && !resultTag.getName().equals(LayoutXml.REFERENCE_BLOCK_ATTRIBUTE_TAG_NAME)) {
+        if (!LayoutXml.BLOCK_ATTRIBUTE_TAG_NAME.equals(resultTag.getName())
+                && !LayoutXml.REFERENCE_BLOCK_ATTRIBUTE_TAG_NAME.equals(resultTag.getName())) {
             return null;
         }
 
         return resultTag;
     }
+
+    /**
+     * Set presentation status.
+     *
+     * @param event AnActionEvent
+     * @param status boolean
+     */
+    private void setStatus(final AnActionEvent event, final boolean status) {
+        event.getPresentation().setVisible(status);
+        event.getPresentation().setEnabled(status);
+    }
 }

src/com/magento/idea/magento2plugin/actions/generation/dialog/InjectAViewModelDialog.java

@@ -104,7 +104,7 @@ protected void textChanged(final @NotNull DocumentEvent event) {
 
         setContentPane(contentPane);
         setModal(true);
-        setTitle(InjectAViewModelAction.actionDescription);
+        setTitle(InjectAViewModelAction.ACTION_DESCRIPTION);
         getRootPane().setDefaultButton(buttonOK);
 
         buttonOK.addActionListener((final ActionEvent event) -> onOK());
@@ -154,7 +154,7 @@ protected void onOK() {
                 getViewModelClassName(),
                 moduleName,
                 namespaceBuilder.getNamespace()
-        ), project).generate(InjectAViewModelAction.actionName, true);
+        ), project).generate(InjectAViewModelAction.ACTION_NAME, true);
         if (viewModel == null) {
             final String errorMessage = validatorBundle.message(
                     "validator.class.alreadyDeclared",