Spring MVC: How to return custom 404 errorpages?

问题:

I'm looking for a clean way to return customized 404 errorpages in Spring 4 when a requested resource was not found. Queries to different domain types should result in different error pages.

Here some code to show my intention (Meter is a domain class):

@RequestMapping(value = "/{number}", method = RequestMethod.GET)
public String getMeterDetails(@PathVariable("number") final Long number, final Model model) {
    final Meter result = meterService.findOne(number);
    if (result == null) {
        // here some code to return an errorpage
    }

    model.addAttribute("meter", result);
    return "meters/details";
}

I imagine several ways for handling the problem. First there would be the possibility to create RuntimeExceptions like

@ResponseStatus(HttpStatus.NOT_FOUND)
public class MeterNotFoundExcption extends RuntimeException { }

and then use an exception handler to render a custom errorpage (maybe containing a link to a list of meters or whatever is appropriate).

But I don't like polluting my application with many small exceptions.

Another possibility would be using HttpServletResponse and set the statuscode manually:

@RequestMapping(value = "/{number}", method = RequestMethod.GET)
public String getMeterDetails(@PathVariable("number") final Long number, final Model model,
final HttpServletResponse response) {
    final Meter meter = meterService.findOne(number);
    if (meter == null) {
        response.setStatus(HttpStatus.NOT_FOUND.value());
        return "meters/notfound";
    }

    model.addAttribute("meter", meter);
    return "meters/details";
}

But with this solution I have to duplicate the first 5 lines for many controller methods (like edit, delete).

Is there an elegant way to prevent duplicating these lines many times?

回答1:

The solution is much simpler than thought. One can use one generic ResourceNotFoundException defined as follows:

public class ResourceNotFoundException extends RuntimeException { }

then one can handle errors within every controller with an ExceptionHandler annotation:

class MeterController {
    // ...
    @ExceptionHandler(ResourceNotFoundException.class)
    @ResponseStatus(HttpStatus.NOT_FOUND)
    public String handleResourceNotFoundException() {
        return "meters/notfound";
    }

    // ...

    @RequestMapping(value = "/{number}/edit", method = RequestMethod.GET)
    public String viewEdit(@PathVariable("number") final Meter meter,
                           final Model model) {
        if (meter == null) throw new ResourceNotFoundException();

        model.addAttribute("meter", meter);
        return "meters/edit";
    }
}

Every controller can define its own ExceptionHandler for the ResourceNotFoundException.

回答2:

modified your web.xml file.Using following code.

<display-name>App Name </display-name>
<error-page>
<error-code>500</error-code>
<location>/error500.jsp</location>
</error-page>

<error-page>
<error-code>404</error-code>
<location>/error404.jsp</location>
</error-page>

Access this by following code.

response.sendError(508802,"Error Message");

Now add this code in web.xml.

<error-page>
<error-code>508802</error-code>
<location>/error500.jsp</location>
</error-page>

回答3:

You can map the error codes in web.xml like the following

    <error-page>
        <error-code>400</error-code>
        <location>/400</location>
    </error-page>

    <error-page>
        <error-code>404</error-code>
        <location>/404</location>
    </error-page>

    <error-page>
        <error-code>500</error-code>
        <location>/500</location>
    </error-page>

Now you can create a controller to map the url's that are hit when any of these error is found.

@Controller
public class HTTPErrorHandler{

    String path = "/error";

    @RequestMapping(value="/404")
    public String error404(){
       // DO stuff here 
        return path+"/404";
    }
    }

For full example see my tutorial about this

回答4:

You should follow this article where you can find detailed information about exception handling in Spring MVC projects.

spring-mvc-exception-handling

@ControllerAdvice may help you in this case

回答5:

We can just add following lines of code into web.xml file and introduce a new jsp file named errorPage.jsp into root directory of the project to get the requirement done.

<error-page>
    <error-code>400</error-code>
    <location>/errorPage.jsp</location>
</error-page>
<error-page>
    <error-code>404</error-code>
    <location>/errorPage.jsp</location>
</error-page>
<error-page>
    <error-code>500</error-code>
    <location>/errorPage.jsp</location>
</error-page>

回答6:

Simple answer for 100% free xml:

1. Set properties for DispatcherServlet

   public class SpringMvcInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {
   
   @Override
   protected Class<?>[] getRootConfigClasses() {
       return new Class[] { RootConfig.class  };
   }
   
   @Override
   protected Class<?>[] getServletConfigClasses() {
       return new Class[] {AppConfig.class  };
   }
   
   @Override
   protected String[] getServletMappings() {
       return new String[] { "/" };
   }
   
   //that's important!!
   @Override
   protected void customizeRegistration(ServletRegistration.Dynamic registration) {
       boolean done = registration.setInitParameter("throwExceptionIfNoHandlerFound", "true"); // -> true
       if(!done) throw new RuntimeException();
   }
   

   }

2. Create @ControllerAdvice:

   @ControllerAdvice
   public class AdviceController {
   
   @ExceptionHandler(NoHandlerFoundException.class)
   public String handle(Exception ex) {
       return "redirect:/404";
   }
   
   @RequestMapping(value = {"/404"}, method = RequestMethod.GET)
   public String NotFoudPage() {
       return "404";
   
   }
   

   }

3. Create 404.jsp page with any content

That's all.

回答7:

I also needed to NOT use org.springframework.web.servlet.config.annotation.DefaultServletHandlerConfigurer.

According to org.springframework.web.servlet.DispatcherServlet.setThrowExceptionIfNoHandlerFound(boolean): "Note that if DefaultServletHttpRequestHandler is used, then requests will always be forwarded to the default servlet and a NoHandlerFoundException would never be thrown in that case."

https://docs.spring.io/spring-framework/docs/current/javadoc-api/org/springframework/web/servlet/DispatcherServlet.html#setThrowExceptionIfNoHandlerFound-boolean-

Before

@Configuration
@EnableWebMvc
@ComponentScan(basePackages = "com.foo.web")
public class WebMvcConfiguration extends WebMvcConfigurerAdapter {

  @Override
  public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
    configurer.enable();
  }

  // ...
}

After

@Configuration
@EnableWebMvc
@ComponentScan(basePackages = "com.foo.web")
public class WebMvcConfiguration extends WebMvcConfigurerAdapter {

  @Override
  public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
  }

  // ...
}