IDEA-174043 Implement method with @NotNull/@Nullable array return type

GitOrigin-RevId: a539db556458ab54411d9b87c40d20e58954382e

java/java-impl/src/com/intellij/codeInsight/generation/GenerateMembersUtil.java

@@ -274,6 +274,12 @@ public class GenerateMembersUtil {
       PsiSubstitutor collisionResolvedSubstitutor =
         substituteTypeParameters(factory, target, sourceMethod.getTypeParameterList(), resultMethod.getTypeParameterList(), substitutor, sourceMethod);
       substituteReturnType(PsiManager.getInstance(project), resultMethod, sourceMethod.getReturnType(), collisionResolvedSubstitutor);
+      PsiTypeElement typeElement = resultMethod.getReturnTypeElement();
+      if (typeElement != null && typeElement.getText().startsWith("@")) {
+        // If return type is annotated, substituteReturnType will add the annotation into type element,
+        // so the method should be reparsed to move it to the modifier list
+        resultMethod = factory.createMethodFromText(resultMethod.getText(), target);
+      }
       substituteParameters(factory, codeStyleManager, sourceMethod.getParameterList(), resultMethod.getParameterList(), collisionResolvedSubstitutor, target);
       copyDocComment(sourceMethod, resultMethod, factory);
       GlobalSearchScope scope = sourceMethod.getResolveScope();

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/implementMethods/afterTypeNullabilityAnnotations.java

@@ -0,0 +1,27 @@
+// "Implement methods" "true"
+package org.jetbrains.annotations;
+
+import java.lang.annotation.*;
+
+@Target({ElementType.METHOD, ElementType.TYPE_USE})
+@interface Nullable{}
+
+@Target({ElementType.METHOD, ElementType.TYPE_USE})
+@interface NotNull{}
+
+interface A {
+    @Nullable Object @NotNull [] getNotNullArrayOfNullableObjects();
+    @NotNull Object @Nullable [] getNullableArrayOfNotNullObjects();
+}
+
+class B implements A {
+    @Override
+    public @Nullable Object @NotNull [] getNotNullArrayOfNullableObjects() {
+        return new Object[0];
+    }
+
+    @Override
+    public @NotNull Object @Nullable [] getNullableArrayOfNotNullObjects() {
+        return new Object[0];
+    }
+}

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/implementMethods/beforeTypeNullabilityAnnotations.java

@@ -0,0 +1,17 @@
+// "Implement methods" "true"
+package org.jetbrains.annotations;
+
+import java.lang.annotation.*;
+
+@Target({ElementType.METHOD, ElementType.TYPE_USE})
+@interface Nullable{}
+
+@Target({ElementType.METHOD, ElementType.TYPE_USE})
+@interface NotNull{}
+
+interface A {
+    @Nullable Object @NotNull [] getNotNullArrayOfNullableObjects();
+    @NotNull Object @Nullable [] getNullableArrayOfNotNullObjects();
+}
+
+class <caret>B implements A {}