HOWTO handle 404 exceptions globally using Spring

问题:

(SOLUTION posted at the end of the Question)

I am building a Spring 4 MVC app. And it is completely configured using Java Annotations. There is no web.xml. The app is configured by using instance of AbstractAnnotationConfigDispatcherServletInitializer and WebMvcConfigurerAdapter like so,

@Configuration
@EnableWebMvc
@ComponentScan(basePackages = {"com.example.*"})
@EnableTransactionManagement
@PropertySource("/WEB-INF/properties/application.properties")
public class WebAppConfig extends WebMvcConfigurerAdapter {
...
}

and

public class WebAppInitializer extends
    AbstractAnnotationConfigDispatcherServletInitializer {
...
}

I am now trying to add a global/catch-all exception handler for 404 pages i.e. HttpStatus.NOT_FOUND but no success. Below are some of the ways I tried.

import org.springframework.http.HttpStatus;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseStatus;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.NoHandlerFoundException;
import org.springframework.web.servlet.mvc.multiaction.NoSuchRequestHandlingMethodException;

@ControllerAdvice
public class GlobalExceptionHandlerController {

    @ExceptionHandler
    @ResponseStatus(HttpStatus.NOT_FOUND)
    public ModelAndView handleException (NoSuchRequestHandlingMethodException ex) {
            ModelAndView mav = new ModelAndView();
            return mav;
    }

    @ExceptionHandler
    @ResponseStatus(HttpStatus.NOT_FOUND)
    public ModelAndView handleExceptiond (NoHandlerFoundException ex) {
            ModelAndView mav = new ModelAndView();
            return mav;
    }

    @ResponseStatus(HttpStatus.NOT_FOUND)
    @ExceptionHandler(NoHandlerFoundException.class)
    public void handleConflict() {

    }

    @ResponseStatus(HttpStatus.NOT_FOUND)
    @ExceptionHandler(NoSuchRequestHandlingMethodException.class)
    public void handlesdConflict() {
    }

}

None of these methods get executed. I am at a loss as to how to handle this. I do not want to use web.xml becasue then I would have to create one just for this.

SOLUTION I did what @Sotirios mentioned here. Here is my portion WebAppInitializer code that will set the dispatcher properly.

public class WebAppInitializer extends
        AbstractAnnotationConfigDispatcherServletInitializer {

    ...

    @Override
    protected void registerDispatcherServlet(ServletContext servletContext) {

        String servletName = super.getServletName();
        Assert.hasLength(servletName, "getServletName() may not return empty or null");

        WebApplicationContext servletAppContext = super.createServletApplicationContext();
        Assert.notNull(servletAppContext,
                "createServletApplicationContext() did not return an application " +
                "context for servlet [" + servletName + "]");

        DispatcherServlet dispatcherServlet = new DispatcherServlet(servletAppContext);

        //>>> START: My custom code, rest is exqact copy of the super class
        dispatcherServlet.setThrowExceptionIfNoHandlerFound(true);
        //>>> END

        ServletRegistration.Dynamic registration = servletContext.addServlet(servletName, dispatcherServlet);
        Assert.notNull(registration,
                "Failed to register servlet with name '" + servletName + "'." +
                "Check if there is another servlet registered under the same name.");

        registration.setLoadOnStartup(1);
        registration.addMapping(getServletMappings());
        registration.setAsyncSupported(isAsyncSupported());

        Filter[] filters = getServletFilters();
        if (!ObjectUtils.isEmpty(filters)) {
            for (Filter filter : filters) {
                super.registerServletFilter(servletContext, filter);
            }
        }

        super.customizeRegistration(registration);
    }

    ...
}

Although I am not particularly happy with this solution because my only custom code is 1 line & rest is directly copied from super class. I wish there was a nicer way to do this.

回答1:

By default, the DispatcherServlet does not throw a NoHandlerFoundException. You need to enable that.

The AbstractAnnotationConfigDispatcherServletInitializer should let you override how the DispatcherServlet is created. Do that and call

DispatcherServlet dispatcherServlet = ...; // might get it from super implementation
dispatcherServlet.setThrowExceptionIfNoHandlerFound(true);

回答2:

Enable DispatcherServlet throw a NoHandlerFoundException through web.xml configuartion.

<init-param>
    <param-name>throwExceptionIfNoHandlerFound</param-name>
    <param-value>true</param-value>
</init-param>

回答3:

Instead overriding registerDispatcherServlet one can override the createDispatcherServlet method as follows.

@Override
    protected DispatcherServlet createDispatcherServlet(WebApplicationContext servletAppContext) {
        DispatcherServlet ds = new DispatcherServlet(servletAppContext);
        ds.setThrowExceptionIfNoHandlerFound(true);
        return ds;
    }

回答4:

I resolved the problem with the following entry in my application.yml

 server.error.whitelabel.enabled: false
 spring.mvc.throw-exception-if-no-handler-found: true

and the following ControllerExceptionHandler:

@ControllerAdvice
public class ControllerExceptionHandler {

@ExceptionHandler(Exception.class)
@ResponseStatus(HttpStatus.BAD_REQUEST)
public String processMethodNotSupportedException(Exception exception) {
    exception.printStackTrace();
    return "error";
}

}

and last but not least i added a template "/html/error.html"

回答5:

I can't comment on the above post by @Ysak (reputation<50), however I can confirm that this method does work with the setup described by the OP.

I will add that from another guide I also had the DefaultServletHandling configured in my WebConfig to fix a separate issue, as below:

@Configuration
@EnableWebMvc
@ComponentScan("com.acme.tat.controllers")
public class WebConfig extends WebMvcConfigurerAdapter implements ApplicationContextAware {
...
@Override
public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
        configurer.enable();
}

}

With this set to enable, there is no Exception thrown. Once I removed this line and set up manual resourceHandlers everything worked as expected.

It took me around 2.5 hours to set up 404 redirecting because of this simple one line method.