SealClassAction: show error if no inheritors for interface + cleanup

GitOrigin-RevId: b5a6dfbf1531dd788eed14a4364cd5431ce8e28e

java/java-impl/src/com/intellij/codeInsight/intention/impl/SealClassAction.java

@@ -71,7 +71,6 @@ public class SealClassAction extends BaseElementAtCaretIntentionAction {
     if (aClass == null) return;
     if (!isAvailable(aClass, editor)) return;
     PsiJavaFile parentFile = (PsiJavaFile)aClass.getContainingFile();
-    FileModificationService.getInstance().prepareFileForWrite(parentFile);
     if (aClass.isInterface()) {
       if (FunctionalExpressionSearch.search(aClass).findFirst() != null) {
         showError(project, editor, "intention.error.make.sealed.class.is.used.in.functional.expression");
@@ -119,12 +118,14 @@ public class SealClassAction extends BaseElementAtCaretIntentionAction {
     }
     else {
       if (aClass.isInterface()) {
-        modifier = PsiModifier.SEALED;
+        showError(project, editor, "intention.error.make.sealed.class.interface.has.no.inheritors");
+        return;
       }
       else {
         modifier = PsiModifier.FINAL;
       }
     }
+    FileModificationService.getInstance().prepareFileForWrite(parentFile);
     ApplicationManager.getApplication().runWriteAction(() -> {
       PsiModifierList modifierList = Objects.requireNonNull(aClass.getModifierList());
       modifierList.setModifierProperty(modifier, true);
@@ -150,7 +151,7 @@ public class SealClassAction extends BaseElementAtCaretIntentionAction {
   }
 
   public void setInheritorsModifiers(@NotNull Project project, List<PsiClass> inheritors) {
-    String title = JavaBundle.message("intention.error.make.sealed.class.task.title.set.inheritors.modifiers");
+    String title = JavaBundle.message("intention.make.sealed.class.task.title.set.inheritors.modifiers");
     SequentialModalProgressTask task = new SequentialModalProgressTask(project, title, true);
     task.setTask(new SequentialTask() {
       private final FileModificationService myFileModificationService = FileModificationService.getInstance();
@@ -207,6 +208,6 @@ public class SealClassAction extends BaseElementAtCaretIntentionAction {
   }
 
   private static String getErrorTitle() {
-    return JavaBundle.message("intention.error.make.sealed.class.hint.title");
+    return JavaBundle.message("intention.make.sealed.class.hint.title");
   }
 }

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/sealClass/failing/InterfaceWithoutInheritors.java

@@ -0,0 +1,2 @@
+interface Par<caret>ent {
+}

java/java-tests/testSrc/com/intellij/java/codeInsight/intention/SealClassActionFailingTest.java

@@ -28,6 +28,10 @@ public class SealClassActionFailingTest extends LightJavaCodeInsightFixtureTestC
     checkErrorMessage(JavaBundle.message("intention.error.make.sealed.class.has.anonymous.or.local.inheritors"));
   }
 
+  public void testInterfaceWithoutInheritors() {
+    checkErrorMessage(JavaBundle.message("intention.error.make.sealed.class.interface.has.no.inheritors"));
+  }
+
   public void testDifferentPackages() {
     myFixture.addFileToProject("foo.java", "package other;\n class Other extends Parent {}");
     checkErrorMessage(JavaBundle.message("intention.error.make.sealed.class.different.packages"));

java/openapi/resources/messages/JavaBundle.properties

@@ -1264,9 +1264,10 @@ intention.name.collapse.into.loop=Collapse into loop
 intention.family.name.make.sealed=Seal class
 intention.name.make.sealed=Make sealed
 intention.error.make.sealed.class.is.used.in.functional.expression=Class is used in functional expression
-intention.error.make.sealed.class.hint.title=Make Sealed
+intention.make.sealed.class.hint.title=Make Sealed
 intention.error.make.sealed.class.has.anonymous.or.local.inheritors=Some of the inheritors are anonymous or local
 intention.error.make.sealed.class.different.packages=Module is unnamed and some of the inheritors are in the different package
 intention.error.make.sealed.class.inheritors.not.in.java.file=Some of the inheritors are not in java files
 intention.error.make.sealed.class.different.modules=Some of the inheritors are in different modules
-intention.error.make.sealed.class.task.title.set.inheritors.modifiers=Setting inheritors modifiers
+intention.error.make.sealed.class.interface.has.no.inheritors=Interface has no inheritors
+intention.make.sealed.class.task.title.set.inheritors.modifiers=Setting inheritors modifiers