Spring boot Zuul Authorization header interceptor

Question

I've created a SpringBoot application my Application.java looks like following

@EnableZuulProxy
@SpringBootApplication
@EnableSwagger2
public class Application {
    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }

    @Bean
    UiConfiguration uiConfig() {
        return new UiConfiguration("validatorUrl", "list", "alpha", "schema",
            UiConfiguration.Constants.DEFAULT_SUBMIT_METHODS, false, true, 60000L);
    }
}

When someone calls any API via Gateway, it has authorization header Authorization: bearer: <token> like this. Now, I need to validate this JWT token.

How do I validate every request for valid JWT token and if incorrect send unauthorized?