Fix default value for enum type in RequestParameter was not added (#10332)

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

@@ -1001,7 +1001,7 @@ public abstract class AbstractJavaCodegen extends DefaultCodegen implements Code
 
     @Override
     public String toDefaultParameterValue(final Schema<?> schema) {
-        Object defaultValue = schema.getDefault();
+        Object defaultValue = schema.get$ref() != null ? ModelUtils.getReferencedSchema(openAPI, schema).getDefault() : schema.getDefault();
         if (defaultValue == null) {
             return null;
         }

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

@@ -690,4 +690,37 @@ public class SpringCodegenTest {
         assertFileContains(Paths.get(outputPath + "/src/main/java/org/openapitools/api/GirafesApi.java"), "allowableValues = \"0, 1\"");
         assertFileContains(Paths.get(outputPath + "/src/main/java/org/openapitools/api/GirafesApi.java"), "@PathVariable");
     }
+
+    @Test
+    public void shouldGenerateDefaultValueForEnumRequestParameter() throws IOException {
+        File output = Files.createTempDirectory("test").toFile().getCanonicalFile();
+        output.deleteOnExit();
+        String outputPath = output.getAbsolutePath().replace('\\', '/');
+
+        final OpenAPI openAPI = TestUtils.parseFlattenSpec("src/test/resources/3_0/spring/issue_10278.yaml");
+        final SpringCodegen codegen = new SpringCodegen();
+        codegen.setOpenAPI(openAPI);
+        codegen.setOutputDir(output.getAbsolutePath());
+
+        codegen.additionalProperties().put(SpringCodegen.DELEGATE_PATTERN, "true");
+        codegen.additionalProperties().put(SpringCodegen.REACTIVE, "true");
+
+        ClientOptInput input = new ClientOptInput();
+        input.openAPI(openAPI);
+        input.config(codegen);
+
+        DefaultGenerator generator = new DefaultGenerator();
+
+        generator.setGeneratorPropertyDefault(CodegenConstants.MODELS, "false");
+        generator.setGeneratorPropertyDefault(CodegenConstants.MODEL_TESTS, "false");
+        generator.setGeneratorPropertyDefault(CodegenConstants.MODEL_DOCS, "false");
+        generator.setGeneratorPropertyDefault(CodegenConstants.APIS, "true");
+        generator.setGeneratorPropertyDefault(CodegenConstants.SUPPORTING_FILES, "false");
+
+        generator.opts(input).generate();
+
+        assertFileContains(Paths.get(outputPath + "/src/main/java/org/openapitools/api/GetApi.java"),
+            "@RequestParam(value = \"testParameter1\", required = false, defaultValue = \"BAR\")",
+            "@RequestParam(value = \"TestParameter2\", required = false, defaultValue = \"BAR\")");
+    }
 }

modules/openapi-generator/src/test/resources/3_0/spring/issue_10278.yaml

@@ -0,0 +1,112 @@
+openapi: 3.0.1
+info:
+  title: Swagger Petstore
+  description: 'This is a sample server Petstore server.  You can find out more about     Swagger
+    at [http://swagger.io](http://swagger.io) or on [irc.freenode.net, #swagger](http://swagger.io/irc/).      For
+    this sample, you can use the api key `special-key` to test the authorization     filters.'
+  termsOfService: http://swagger.io/terms/
+  contact:
+    email: apiteam@swagger.io
+  license:
+    name: Apache 2.0
+    url: http://www.apache.org/licenses/LICENSE-2.0.html
+  version: 1.0.0
+externalDocs:
+  description: Find out more about Swagger
+  url: http://swagger.io
+servers:
+  - url: https://petstore.swagger.io/v2
+  - url: http://petstore.swagger.io/v2
+tags:
+  - name: pet
+    description: Everything about your Pets
+    externalDocs:
+      description: Find out more
+      url: http://swagger.io
+  - name: store
+    description: Access to Petstore orders
+  - name: user
+    description: Operations about user
+    externalDocs:
+      description: Find out more about our store
+      url: http://swagger.io
+paths:
+  /get:
+    put:
+      tags:
+        - pet
+      summary: Update an existing pet
+      operationId: getPet
+      parameters:
+        - $ref: '#/components/parameters/TestParameter1'
+        - in: query
+          name: TestParameter2
+          schema:
+            type: string
+            enum: [ FOO, BAR ]
+            default: BAR
+      responses:
+        400:
+          description: Invalid ID supplied
+          content: {}
+        404:
+          description: Pet not found
+          content: {}
+        405:
+          description: Validation exception
+          content: {}
+      security:
+        - petstore_auth:
+            - write:pets
+            - read:pets
+      x-codegen-request-body-name: body
+
+components:
+  parameters:
+    TestParameter1:
+      name: testParameter1
+      in: query
+      description: |
+        Type of token
+      schema:
+        $ref: '#/components/schemas/TestParameter1'
+  schemas:
+    TestParameter1:
+      type: string
+      enum:
+        - FOO
+        - BAR
+      default: BAR
+    Category:
+      type: object
+      properties:
+        id:
+          type: integer
+          format: int64
+        name:
+          type: string
+      xml:
+        name: Category
+    Tag:
+      type: object
+      properties:
+        id:
+          type: integer
+          format: int64
+        name:
+          type: string
+      xml:
+        name: Tag
+  securitySchemes:
+    petstore_auth:
+      type: oauth2
+      flows:
+        implicit:
+          authorizationUrl: http://petstore.swagger.io/oauth/dialog
+          scopes:
+            write:pets: modify pets in your account
+            read:pets: read your pets
+    api_key:
+      type: apiKey
+      name: api_key
+      in: header