Register Spring HandlerInterceptor Without WebMvcConfigurationSupport

Question

I'm trying to register an instance of HandlerInterceptor in Spring using Java Config without extending WebMvcConfigurationSupport. I'm creating a library with an annotation that, when added to a @Configuration class, registers an interceptor that handles a security annotation.

I had an implementation using WebMvcConfigurationSupport#addInterceptors, but that conflicted with other automatic workings in spring, and overrode some of the application's own logic. It also seems incredibly heavy for something that should be simple. I'm now trying:

@Configuration
public class AnnotationSecurityConfiguration {

    @Autowired private RequestMappingHandlerMapping requestMappingHandlerMapping;

    @PostConstruct
    public void attachInterceptors() {
        requestMappingHandlerMapping.setInterceptors(new Object[] {
                new SecurityAnnotationHandlerInterceptor()
        });
    }

}

However, it appears that the interceptor gets registered with a completely different instance of RequestMappingHandlerMapping than the one the application actually uses for web requests. Additionally, when implemeted as a BeanFactoryPostProcessor, I get a NullPointerException in HealthMvcEndpoint when I try beanFactory.getBean(RequestMappingHandlerMapping.class)

Answer 1

Just stating @Blauhirn's comment, WebMvcConfigurerAdapter is deprecated as of version 5.0:

Deprecated as of 5.0 WebMvcConfigurer has default methods (made possible by a Java 8 baseline) and can be implemented directly without the need for this adapter

Refer to the new way to do it:

@Configuration
public class WebMvcConfig implements WebMvcConfigurer {

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(new MyCustomInterceptor())
        // Optional
        .addPathPatterns("/myendpoint");
    }
}

---

Plus, as stated here, do not annotate this with @EnableWebMvc, if you want to keep Spring Boot auto configuration for MVC.

Answer 2

Edit: This class has since been deprecated. See @bosco answer below for the Spring 5 equivalent.

Figured it out, the solution is to use, simply:

@Configuration
public class AnnotationSecurityConfiguration extends WebMvcConfigurerAdapter {

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(new SecurityAnnotationHandlerInterceptor());
    }

}

In spring boot, all beans of type WebMvcConfigurer are automatically detected and can modify the MVC context.