Is there any way to inject Interceptor from external library in Spring?

June 21, 2022, at 00:30 AM

I'm developing a jar library and trying to inject an interceptor from external jar library to Application.

For example:

External Lib

MyExternalInterceptor.java

public class MyExternalInterceptor implements HandlerInterceptor {
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        // Do something
    }
}

I tried to using AOP in external libs but it's not working.

InterceptorAspect.java

@Around("execution(* org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport.addInterceptors(..))")
public Object aspect(ProceedingJoinPoint proceedingJoinPoint) throws Throwable {
    // Tried to inject MyExternalInterceptor here
    Object result = proceedingJoinPoint.proceed();
    return result;
}

In Application using that lib:

Application

MyConfiguration.java

@Configuration
public MyConfiguration extends WebMvcConfigurationSupport {
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(new SpringTestInterceptor()); // client's own interceptor
        /* Add MyExternalInterceptor not explicitly but implicitly using AOP or other things */
    }
}

Is there any way to inject an interceptor from external lib to App?

I know the question is very obscure (sorry for that), but could you give me any advice or hint to make it work?

Thank you for anyone who read my question :)

(I updated few more details for clarification)

Answer 1

Summary

Use WebMvcConfigurer in both Client and library side instead of WebMvcConfigurationSupport
AoP is not needed

I use WebMvcConfigurer instead of WebMvcConfigurationSupport and change some codes like below:

External Lib

MyExternalInterceptor.java

Same as before

InterfaceAspect.java

Don't needed it anymore

MyExternalLibConfiguration.java

@Configuration
public class MyExternalLibConfiguration implements WebMvcConfigurer {
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(new MyExternalInterceptor());
    }
}

Application (client)

MyConfiguration.java

@Configuration
public MyConfiguration implements WebMvcConfigurer {
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(new SpringTestInterceptor()); // client's own interceptor
        /* No need to add MyExternalInterceptor in here */
    }
}

That's all! Everything is working well as M. Deinum said in comment.

Thank you again Deinum!