support also list format

Author: Picazsoo

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/KotlinSpringServerCodegen.java

@@ -966,13 +966,19 @@ public CodegenOperation fromOperation(String path, String httpMethod, Operation
                 if (DocumentationProvider.SPRINGDOC.equals(getDocumentationProvider())) {
                     codegenOperation.imports.add("PageableAsQueryParam");
                     // Prepend @PageableAsQueryParam to existing x-operation-extra-annotation if present
+                    // Use getObjectAsStringList to properly handle both list and string formats:
+                    // - YAML list: ['@Ann1', '@Ann2'] -> List of annotations
+                    // - Single string: '@Ann1 @Ann2' -> Single-element list
+                    // - Nothing/null -> Empty list
                     Object existingAnnotation = codegenOperation.vendorExtensions.get("x-operation-extra-annotation");
-                    if (existingAnnotation != null && !existingAnnotation.toString().isEmpty()) {
-                        codegenOperation.vendorExtensions.put("x-operation-extra-annotation",
-                            "@PageableAsQueryParam\n    " + existingAnnotation);
-                    } else {
-                        codegenOperation.vendorExtensions.put("x-operation-extra-annotation", "@PageableAsQueryParam");
-                    }
+                    List<String> annotations = DefaultCodegen.getObjectAsStringList(existingAnnotation);
+
+                    // Prepend @PageableAsQueryParam to the beginning of the list
+                    List<String> updatedAnnotations = new ArrayList<>();
+                    updatedAnnotations.add("@PageableAsQueryParam");
+                    updatedAnnotations.addAll(annotations);
+
+                    codegenOperation.vendorExtensions.put("x-operation-extra-annotation", updatedAnnotations);
                 }
 
                 // #8315 Remove matching Spring Data Web default query params if 'x-spring-paginated' with Pageable is used
@@ -1228,6 +1234,7 @@ public List<VendorExtension> getSupportedVendorExtensions() {
         extensions.add(VendorExtension.X_CONTENT_TYPE);
         extensions.add(VendorExtension.X_DISCRIMINATOR_VALUE);
         extensions.add(VendorExtension.X_FIELD_EXTRA_ANNOTATION);
+        extensions.add(VendorExtension.X_OPERATION_EXTRA_ANNOTATION);
         extensions.add(VendorExtension.X_PATTERN_MESSAGE);
         extensions.add(VendorExtension.X_SIZE_MESSAGE);
         extensions.add(VendorExtension.X_MINIMUM_MESSAGE);

modules/openapi-generator/src/test/java/org/openapitools/codegen/kotlin/spring/KotlinSpringServerCodegenTest.java

@@ -3961,6 +3961,54 @@ public void springPaginatedWithSpringDocPrependsToExistingAnnotation() throws Ex
         assertFileContains(petApi.toPath(), "@Parameter(hidden = true) pageable: Pageable");
     }
 
+    @Test
+    public void springPaginatedWithSpringDocPrependsToExistingAnnotationArray() throws Exception {
+        Map<String, Object> additionalProperties = new HashMap<>();
+        additionalProperties.put(USE_TAGS, "true");
+        additionalProperties.put(DOCUMENTATION_PROVIDER, "springdoc");
+        additionalProperties.put(INTERFACE_ONLY, "true");
+        additionalProperties.put(SKIP_DEFAULT_INTERFACE, "true");
+
+        Map<String, File> files = generateFromContract("src/test/resources/3_0/spring/petstore-with-spring-pageable.yaml", additionalProperties);
+
+        File petApi = files.get("PetApi.kt");
+        String content = Files.readString(petApi.toPath());
+
+        // Verify that PageableAsQueryParam is imported
+        assertFileContains(petApi.toPath(), "import org.springdoc.core.converters.models.PageableAsQueryParam");
+
+        // Find the findPetsByStatus method
+        int findPetsByStatusStart = content.indexOf("fun findPetsByStatus(");
+        Assert.assertTrue(findPetsByStatusStart > 0, "findPetsByStatus method should exist");
+
+        // Check the annotations appear before the method in the correct order
+        String methodBlock = content.substring(Math.max(0, findPetsByStatusStart - 1500), findPetsByStatusStart);
+
+        int pageableAsQueryParamPos = methodBlock.lastIndexOf("@PageableAsQueryParam");
+        int validatedPos = methodBlock.lastIndexOf("@org.springframework.validation.annotation.Validated");
+        int preAuthorizePos = methodBlock.lastIndexOf("@org.springframework.security.access.prepost.PreAuthorize");
+        int requestMappingPos = methodBlock.lastIndexOf("@RequestMapping");
+
+        Assert.assertTrue(pageableAsQueryParamPos > 0, "@PageableAsQueryParam should be present before findPetsByStatus method");
+        Assert.assertTrue(validatedPos > 0, "@Validated should be present before findPetsByStatus method");
+        Assert.assertTrue(preAuthorizePos > 0, "@PreAuthorize should be present before findPetsByStatus method");
+
+        // Verify @PageableAsQueryParam comes first (prepended to the array)
+        Assert.assertTrue(pageableAsQueryParamPos < validatedPos,
+            "@PageableAsQueryParam should be prepended (appear before) @Validated annotation");
+
+        // Verify the original array order is preserved after @PageableAsQueryParam
+        Assert.assertTrue(validatedPos < preAuthorizePos,
+            "@Validated should appear before @PreAuthorize (original array order preserved)");
+
+        // Verify all annotations come before @RequestMapping
+        Assert.assertTrue(preAuthorizePos < requestMappingPos,
+            "All annotations should appear before @RequestMapping");
+
+        // Verify the Pageable parameter still has @Parameter(hidden = true)
+        assertFileContains(petApi.toPath(), "@Parameter(hidden = true) pageable: Pageable");
+    }
+
     @Test
     public void springPaginatedMixedOperations() throws Exception {
         Map<String, Object> additionalProperties = new HashMap<>();

modules/openapi-generator/src/test/resources/3_0/spring/petstore-with-spring-pageable.yaml

@@ -117,6 +117,9 @@ paths:
         - write:pets
         - read:pets
       x-spring-paginated: true
+      x-operation-extra-annotation:
+        - "@org.springframework.validation.annotation.Validated"
+        - "@org.springframework.security.access.prepost.PreAuthorize(\"hasRole('ADMIN')\")"
   /pet/findByTags:
     get:
       tags:

samples/openapi3/client/petstore/spring-cloud-spring-pageable/src/main/java/org/openapitools/api/PetApi.java

@@ -239,6 +239,7 @@ ResponseEntity<Pet> getPetById(
         value = PetApi.PATH_LIST_ALL_PETS,
         produces = { "application/json", "application/xml" }
     )
+    @org.springframework.validation.annotation.Validated
     ResponseEntity<List<Pet>> listAllPets(
         @ParameterObject final Pageable pageable
     );