mvc.pathmatch.matching-strategy=ant_path_matcher does not get applied by spring boot

I am in the process of migrating Springboot from 2.5 to 3.4 (it sits at 3.0 at the time of recording)

and one thing that changes is that the ant path matcher is no longer the default, therefore i added this to my application.yaml

spring:
  mvc:
    pathmatch:
      matching-strategy: ant_path_matcher

which usually solves the problem which i have done multiple times. but the Error persists.

This is the WebMvcConfig.kt file:

package our.application.path.configuration

import com.fasterxml.jackson.databind.ObjectMapper
import org.springframework.context.annotation.Bean
import org.springframework.context.annotation.Configuration
import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter
import org.springframework.web.cors.CorsConfiguration
import org.springframework.web.cors.CorsConfigurationSource
import org.springframework.web.cors.UrlBasedCorsConfigurationSource
import org.springframework.web.servlet.config.annotation.EnableWebMvc
import org.springframework.web.servlet.config.annotation.ViewControllerRegistry
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer

@Configuration
@EnableWebMvc
class WebMvcConfig : WebMvcConfigurer {
    companion object {
        // Forwarding target
        const val FORWARD_INDEX_HTML = "forward:/index.html"
    }

    override fun addViewControllers(registry: ViewControllerRegistry) {
        // Map "/" to /index.html
        registry.addViewController("/").setViewName(FORWARD_INDEX_HTML)

        // Single directory level - no need to exclude "api"
        registry.addViewController("/{x:[\\w\\-]+}").setViewName(FORWARD_INDEX_HTML)
        // Multi-level directory path, need to exclude "api" on the first part of the path
        registry.addViewController("/{x:^(?!api$).*$}/**/{y:[\\w\\-]+}").setViewName(FORWARD_INDEX_HTML)
    }

    @Bean
    fun corsConfigurationSource(): CorsConfigurationSource {
        val source = UrlBasedCorsConfigurationSource()
        source.registerCorsConfiguration("/**", CorsConfiguration().applyPermitDefaultValues())
        return source
    }


    @Bean
    open fun mappingJackson2HttpMessageConverter(objectMapper: ObjectMapper): MappingJackson2HttpMessageConverter {
        return MappingJackson2HttpMessageConverter(objectMapper)
    }
}

The Error occurs with or without the added fix in the yaml file and occurs at the end of the application start:

2025-05-22 16:56:15.229  INFO 29128 --- [           main] s.w.a.s.ProblemSecurityBeanPostProcessor [] : Register HttpSecurity's exceptionHandling
2025-05-22 16:56:15.289  WARN 29128 --- [           main] ConfigServletWebServerApplicationContext [] : Exception encountered during context initialization - cancelling refresh attempt:
 org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'publicApiFilterChain' defined in class path resource [our/application/path/configuration/SecurityConfig.class]:
 Unsatisfied dependency expressed through method 'publicApiFilterChain' parameter 1: Error creating bean with name 'mvc' defined in class path resource 
[our/application/path/configuration/SecurityConfig.class]: Unsatisfied dependency expressed through method 'mvc' parameter 0: Error creating bean with name 'mvcHandlerMappingIntrospector' defined in class path resource 
[org/springframework/web/servlet/config/annotation/DelegatingWebMvcConfiguration.class]: Error creating bean with name 'viewControllerHandlerMapping' defined in class path resource 
[org/springframework/web/servlet/config/annotation/DelegatingWebMvcConfiguration.class]: No more pattern data allowed after {*...} or ** pattern element
2025-05-22 16:56:15.290  INFO 29128 --- [           main] j.LocalContainerEntityManagerFactoryBean [] : Closing JPA EntityManagerFactory for persistence unit 'default'
2025-05-22 16:56:15.291  INFO 29128 --- [           main] com.zaxxer.hikari.HikariDataSource       [] : HikariPool-1 - Shutdown initiated...
2025-05-22 16:56:15.304  INFO 29128 --- [           main] com.zaxxer.hikari.HikariDataSource       [] : HikariPool-1 - Shutdown completed.
2025-05-22 16:56:15.306  INFO 29128 --- [           main] o.apache.catalina.core.StandardService   [] : Stopping service [Tomcat]
2025-05-22 16:56:15.319  INFO 29128 --- [           main] .s.b.a.l.ConditionEvaluationReportLogger [] : 

Error starting ApplicationContext. To display the condition evaluation report re-run your application with 'debug' enabled.
2025-05-22 16:56:15.332 ERROR 29128 --- [           main] o.s.b.d.LoggingFailureAnalysisReporter   [] : 

***************************
APPLICATION FAILED TO START
***************************

Description:

Invalid mapping pattern detected: /{x:^(?!api$).*$}/**/{y:[\w\-]+}
                 ^
No more pattern data allowed after {*...} or ** pattern element

Action:

Fix this pattern in your application or switch to the legacy parser implementation with 'spring.mvc.pathmatch.matching-strategy=ant_path_matcher'.


Process finished with exit code 1

Additional Info: I have:

looked up the problem on google and stack overlow
looked asked ai(Chatgpt) about it
Checked multiple times if it is the same as in other working projects
asked multiple colleges

for further information feel free to ask

Solution

All spring.mvc.* properties are applied by Spring Boot's auto-configuration for Spring MVC. You have annotated your WebMvcConfig class with @EnableWebMvc which disables Spring Boot's auto-configuration for Spring MVC. As a result, the spring.mvc.pathmatch.matching-strategy property is ignored.

You should be able to fix the problem by removing @EnableWebMvc from WebMvcConfig. It implements WebMvcConfigurer so it will still be called to fine-tune Spring MVC's configuration.