How to migrate from AnnotationMethodHandlerAdapter to RequestMappingHandlerAdapter - spring

Question

I'm building REST services via Spring MVC in the application where the GUI is managed by Wicket. Basically, all I need is the DispatcherServlet and a controller with #RequestMapping/#RequestBody.
Because services serve JSON, I need to set MappingJackson2HttpMessageConverter. I can do this via AnnotationMethodHandlerAdapter and that works fine:
#Configuration
#ComponentScan("cz.swsamuraj.wicketspring")
public class SpringRestConfiguration {
#Bean
public AnnotationMethodHandlerAdapter annotationMethodHandlerAdapter() {
HttpMessageConverter<?>[] converters = { new MappingJackson2HttpMessageConverter()};
AnnotationMethodHandlerAdapter adapter = new AnnotationMethodHandlerAdapter();
adapter.setMessageConverters(converters);
return adapter;
}
}
The problem is that AnnotationMethodHandlerAdapter is deprecated and it's recommended to use RequestMappingHandlerAdapter instead.
But if I use this configuration:
#Configuration
#ComponentScan("cz.swsamuraj.wicketspring")
public class SpringRestConfiguration {
#Bean
public RequestMappingHandlerAdapter requestHandler() {
RequestMappingHandlerAdapter adapter = new RequestMappingHandlerAdapter();
adapter.getMessageConverters().add(new MappingJackson2HttpMessageConverter());
return adapter;
}
}
I receive an exception:
javax.servlet.ServletException: No adapter for handler [cz.swsamuraj.wicketspring.ws.api.QuestionApiController#69f8a79f]: The DispatcherServlet configuration needs to include a HandlerAdapter that supports this handler
at org.springframework.web.servlet.DispatcherServlet.getHandlerAdapter(DispatcherServlet.java:1198)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:943)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:897)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:861)
So, my question is: how can I set up a handler adapter in the RequestMappingHandlerAdapter?
I spent couple of days of research, but I didn't find any useful example of how to configure RequestMappingHandlerAdapter. All the advices just says to put #EnableWebMvc on the configuration, but this is not the way because of this Wicket-Spring coexistence.
Just to provide a full context, I've created a small buildable and runnable project on Bitbucket: sw-samuraj/blog-wicket-spring-rest

Answer 1

I was able to solve my problem with different approach - with usage of WebApplicationInitializer, I was able to put the #EnableWebMvc annotation on my configuration class and therefore neither the bean RequestMappingHandlerAdapter, nor AnnotationMethodHandlerAdapter are necessary. JSON now works fine, out-of-the-box.
Configuration
#Configuration
#EnableWebMvc
#ComponentScan("cz.swsamuraj.wicketspring")
public class SpringRestConfiguration {
// some additional beans needed for business logic
}
WebApplicationInitializer
public class WebAppInitializer implements WebApplicationInitializer {
#Override
public void onStartup(ServletContext servletContext) throws ServletException {
AnnotationConfigWebApplicationContext dispatcherContext = new AnnotationConfigWebApplicationContext();
dispatcherContext.register(SpringRestConfiguration.class);
servletContext.addListener(new ContextLoaderListener(dispatcherContext));
ServletRegistration.Dynamic dispatcher =
servletContext.addServlet("dispatcher", new DispatcherServlet(dispatcherContext));
dispatcher.setLoadOnStartup(1);
dispatcher.addMapping("/rest/*");
}
}
Example project
Complete working example is on Bitbucket: blog-wicket-spring-rest