Validation not working for generated code using swagger codegen for spring boot app

Question

Description

Validations are not working at runtime. I am using spring boot - 3.1.4 and swagger-codegen-maven-plugin - 2.4.32. My configuration is as below :

<plugin>
   <groupId>io.swagger</groupId>
   <artifactId>swagger-codegen-maven-plugin</artifactId>
   <version>2.4.32</version>
   <executions>
       <execution>
           <id>swagger-codegen</id>
           <phase>generate-sources</phase>
           <goals>
               <goal>generate</goal>
           </goals>
           <configuration>
               <inputSpec>${project.build.directory}/BOOT-INF/classes/${serviceYamlName}.yaml</inputSpec>
               <language>spring</language>
               <apiPackage>com.k2.openapi.${serviceName}.api</apiPackage>
               <modelPackage>com.k2.openapi.${serviceName}.model</modelPackage>
               <configOptions>
                   <delegatePattern>true</delegatePattern>
                   <hideGenerationTimestamp>true</hideGenerationTimestamp>
                   <useBeanValidation>true</useBeanValidation>
                   <performBeanValidation>true</performBeanValidation>
                   <library>spring-mvc</library>
               </configOptions>
               <addCompileSourceRoot>true</addCompileSourceRoot>
               <generateSupportingFiles>false</generateSupportingFiles>
           </configuration>
       </execution>
   </executions>
</plugin>

However at runtime, bean validations are not performed for required fields.

Generated interface method has @valid annotation:

ResponseEntity\<Void\> createUser(@ApiParam(value = "Created user object" ,required=true )
  
@Valid 
@RequestBody 
User body);

Generated POJO has @validated annotation:

@Validated
public class User   {

However, I do not see any generated message for required fields :

@ApiModelProperty(required = true, value = "")
@NotNull
public Long getId() {
  return id;
}

Swagger-codegen version

2.4.32

Swagger declaration file content or url

swagger: "2.0"
info:
  title: Reflectoring
  description: "Tutorials on Spring Boot and Java, thoughts about the Software Craft, and relevant book reviews. Because it's just as important to understand the Why as it is to understand the How. Have fun!"
  version: 0.0.1-SNAPSHOT
termsOfService: http://swagger.io/terms/
contact:
  email: [email protected]
license:
  name: Apache 2.0
  url: http://www.apache.org/licenses/LICENSE-2.0.html
externalDocs:
  description: Find out more about Reflectoring
  url: https://reflectoring.io/about/
host: reflectoring.swagger.io
basePath: /v2
tags:
  - name: user
    description: Operations about user
paths:
  /user:
    post:
      tags:
        - user
      summary: Create user
      description: Create user functionality
      operationId: createUser
      consumes:
        - application/json
      produces:
        - application/json
      parameters:
        - in: body
          name: body
          description: Created user object
          required: true
          schema:
            $ref: '#/definitions/User'
      responses:
        "default":
          description: successful operation
  /user/{username}:
    get:
      tags:
        - user
      summary: Get user by user name
      description: Get user functionality
      operationId: getUserByName
      produces:
        - application/json
      parameters:
        - name: username
          in: path
          description: "The name that needs to be fetched. Use user1 for testing."
          required: true
          type: string
      responses:
        "200":
          description: successful operation
          schema:
            $ref: '#/definitions/User'
        "404":
          description: User not found
    put:
      tags:
        - user
      summary: Updated user
      description: This can only be done by the logged in user.
      operationId: updateUser
      consumes:
        - application/json
      produces:
        - application/json
      parameters:
        - name: username
          in: path
          description: name that need to be updated
          required: true
          type: string
        - in: body
          name: body
          description: Updated user object
          required: true
          schema:
            $ref: '#/definitions/User'
      responses:
        "200":
          description: successful operation
          schema:
            $ref: '#/definitions/User'
        "400":
          description: Invalid user supplied
        "404":
          description: User not found
    delete:
      tags:
        - user
      summary: Delete user
      description: This can only be done by the logged in user.
      operationId: deleteUser
      produces:
        - application/json
      parameters:
        - name: username
          in: path
          description: The name that needs to be deleted
          required: true
          type: string
      responses:
        "201":
          description: operation successful
        "400":
          description: Invalid username supplied
        "404":
          description: User not found
definitions:
  User:
    type: object
    required:
      - id
      - username
    properties:
      id:
        type: integer
        format: int64
      username:
        type: string
      firstName:
        type: string
      lastName:
        type: string
      email:
        type: string
      password:
        type: string
      phone:
        type: string
      userStatus:
        type: integer
        description: User Status
        format: int32

I tried downgrading spring boot and swagger code gen plugin version. Also tried with jakarta instead of javax but generated code has javax.