使用 Java 配置在 Spring 中重定向 404 错误

Question

如你所知，在 XML 中，配置它的方式是：

<error-page>
    <error-code>404</error-code>
    <location>/my-custom-page-not-found.html</location>
</error-page>

但我还没有找到在 Java 配置中执行此操作的方法。我尝试的第一种方法是：

@RequestMapping(value = "/**")
public String Error(){
    return "error";
}

它似乎可以工作，但是在检索资源时会发生冲突。

有办法吗？

Answer 1

在 Spring Framework 中，有多种处理异常的方法（尤其是 404 错误）。这是documentation link。

• 首先，您仍然可以在web.xml中使用error-page标签，并自定义错误页面。这是example。

• 其次，您可以为所有控制器使用一个@ExceptionHandler，如下所示：

  @ControllerAdvice
  public class ControllerAdvisor {
  
       @ExceptionHandler(NoHandlerFoundException.class)
       public String handle(Exception ex) {
  
          return "404";//this is view name
      }
  }
  

  为此，请将 web.xml 中 DispatcherServlet 的 throwExceptionIfNoHandlerFound 属性设置为 true：

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

  您还可以将一些对象传递给错误视图，请参阅javadoc。

Answer 2

自 spring 4.2 RC3 以来最干净的解决方案是在扩展 AbstractDispatcherServletInitializer（或间接通过扩展 AbstractAnnotationConfigDispatcherServletInitializer）的类中使用新的 createDispatcherServlet 挂钩，如下所示：

public class WebAppInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {
    @Override
    protected Class<?>[] getRootConfigClasses() {
        return null;
    }

    /* ... */

    @Override
    protected DispatcherServlet createDispatcherServlet(WebApplicationContext servletAppContext) {
        final DispatcherServlet dispatcherServlet = super.createDispatcherServlet(servletAppContext);
        dispatcherServlet.setThrowExceptionIfNoHandlerFound(true);
        return dispatcherServlet;
    }
}

然后您可以使用全局@ControllerAdvice（一个用@ControllerAdvice 注释的类），如in the reference docs 所述。在建议中，您可以使用@ExceptionHandler 处理NoHandlerFoundException，如here 所述。

这可能看起来像这样：

@ControllerAdvice
public class NoHandlerFoundControllerAdvice {

    @ExceptionHandler(NoHandlerFoundException.class)
    public ResponseEntity<String> handleNoHandlerFoundException(NoHandlerFoundException ex) {
        // prepare responseEntity
        return responseEntity;
    }

}

Answer 3

按照in the doc 的描述使用基于代码的 Servlet 容器初始化并覆盖 registerDispatcherServlet 方法以将 throwExceptionIfNoHandlerFound 属性设置为 true：

public class WebAppInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {
    @Override
    protected Class<?>[] getRootConfigClasses() {
        return null;
    }

    @Override
    protected Class<?>[] getServletConfigClasses() {
        return new Class[] { WebConfig.class };
    }

    @Override
    protected String[] getServletMappings() {
        return new String[] { "/" };
    }

    @Override
    protected void registerDispatcherServlet(ServletContext servletContext) {
        String servletName = getServletName();
        Assert.hasLength(servletName, "getServletName() may not return empty or null");

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

        DispatcherServlet dispatcherServlet = new DispatcherServlet(servletAppContext);

        // throw NoHandlerFoundException to Controller
        dispatcherServlet.setThrowExceptionIfNoHandlerFound(true);

        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) {
                registerServletFilter(servletContext, filter);
            }
        }

        customizeRegistration(registration);
    }
}    

然后创建一个异常处理程序：

@ControllerAdvice
public class ExceptionHandlerController {
    @ExceptionHandler(Exception.class)
    public String handleException(Exception e) {
        return "404";// view name for 404 error
    }   
}

不要忘记在 Spring configuration file 上使用 @EnableWebMvc 注释：

@Configuration
@EnableWebMvc
@ComponentScan(basePackages= {"org.project.etc"})
public class WebConfig extends WebMvcConfigurerAdapter {
    ...
}

Answer 4

100% 免费 xml 的简单答案：

1. 为DispatcherServlet设置属性

   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[] { "/" };
       }
   
       @Override
       protected void customizeRegistration(ServletRegistration.Dynamic registration) {
           boolean done = registration.setInitParameter("throwExceptionIfNoHandlerFound", "true"); // -> true
           if(!done) throw new RuntimeException();
       }
   
   }
   

2. 创建@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";
   
       }
   }
   

Answer 5

在您的网络配置类中，

@Configuration
public class WebConfig extends WebMvcConfigurerAdapter 

如下声明一个bean，

@Bean
public EmbeddedServletContainerCustomizer containerCustomizer() {

  return new EmbeddedServletContainerCustomizer() {
    @Override
    public void customize(ConfigurableEmbeddedServletContainer container)       
    {
      ErrorPage error401Page = new ErrorPage(HttpStatus.UNAUTHORIZED, "/401.html");
      ErrorPage error404Page = new ErrorPage(HttpStatus.NOT_FOUND, "/404.html");
      ErrorPage error500Page = new ErrorPage(HttpStatus.INTERNAL_SERVER_ERROR, "/500.html");

      container.addErrorPages(error401Page,error404Page,error500Page);
    }
  };
}

将提到的html文件（401.html.etc）添加到/src/main/resources/static/文件夹中。

希望对你有帮助

Answer 6

对于 Java 配置，DispatcherServlet 中有一个方法 setThrowExceptionIfNoHandlerFound(boolean throwExceptionIfNoHandlerFound)。通过将其设置为true 我猜你正在做同样的事情

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

那么您可以在控制器建议中使用NoHandlerFoundException.class，如上述答案所述

它会像什么东西

public class WebXml implements WebApplicationInitializer{

    public void onStartup(ServletContext servletContext) throws ServletException {
        WebApplicationContext context = getContext();
        servletContext.addListener(new ContextLoaderListener(context));


        DispatcherServlet dp =  new DispatcherServlet(context);
        dp.setThrowExceptionIfNoHandlerFound(true);

        ServletRegistration.Dynamic dispatcher = servletContext.addServlet("DispatcherServlet", dp);
        dispatcher.setLoadOnStartup(1);
        dispatcher.addMapping(MAPPING_URL);
    }
}

Answer 7

in comments above 提出的解决方案确实有效：

@Override
protected void customizeRegistration(ServletRegistration.Dynamic registration)
{
  registration.setInitParameter("throwExceptionIfNoHandlerFound", "true");
}

Answer 8

Spring 5 和 Thymeleaf 3 的解决方案。

在MyWebInitializer 中，使用setThrowExceptionIfNoHandlerFound() 启用异常抛出。我们需要对DispatcherServlet进行强制转换。

@Configuration
public class MyWebInitializer extends
        AbstractAnnotationConfigDispatcherServletInitializer {

        ...

        @Override
        protected FrameworkServlet createDispatcherServlet(WebApplicationContext servletAppContext) {
            var dispatcher = (DispatcherServlet) super.createDispatcherServlet(servletAppContext);
            dispatcher.setThrowExceptionIfNoHandlerFound(true);
            return dispatcher;
        }
    }

使用@ControllerAdvice 创建控制器建议并将错误消息添加到ModealAndView。

@ControllerAdvice
public class ControllerAdvisor {

    @ExceptionHandler(NoHandlerFoundException.class)
    public ModelAndView handle(Exception ex) {

        var mv = new ModelAndView();
        mv.addObject("message", ex.getMessage());
        mv.setViewName("error/404");

        return mv;
    }
}

创建 404 错误模板，显示错误消息。根据我的配置，文件是src/main/resources/templates/error/404.html。

<!doctype html>
<html xmlns:th="http://www.thymeleaf.org">
<head>
    <meta charset="UTF-8">
    <meta name="viewport"
          content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <title>Resource not found</title>
</head>
<body>

<h2>404 - resource not found</h2>

<p>
    <span th:text="${message}" th:remove="tag"></span>
</p>

</body>
</html>

为了完整起见，我添加了 Thymeleaf 解析器配置。我们将 Thymeleaf 模板配置在类路径上的 templates 目录中。

@Configuration
@EnableWebMvc
@ComponentScan(basePackages = {"com.zetcode"})
public class WebConfig implements WebMvcConfigurer {

    @Autowired
    private ApplicationContext applicationContext;

    ...

    @Bean
    public SpringResourceTemplateResolver templateResolver() {

        var templateResolver = new SpringResourceTemplateResolver();

        templateResolver.setApplicationContext(applicationContext);
        templateResolver.setPrefix("classpath:/templates/");
        templateResolver.setSuffix(".html");

        return templateResolver;
    }
    ...
}

Answer 9

在 springboot 中它更简单。由于 Spring 自动配置的东西，spring 创建了一个 bean org.springframework.boot.autoconfigure.web.servlet.WebMvcProperties。这个类用@ConfigurationProperties(prefix = "spring.mvc")注解，因此它会寻找带有spring.mvc前缀的属性。

部分来自 javadoc：

Annotation for externalized configuration. Add this to a class definition or a
* @Bean method in a @Configuration class if you want to bind and validate
* some external Properties (e.g. from a .properties file).

您只需将以下属性添加到您的即application.properties 文件中：

 spring.mvc.throwExceptionIfNoHandlerFound=true
 spring.resources.add-mappings=false //this is for spring so it won't return default handler for resources that not exist

并添加异常解析器如下：

@ControllerAdvice
public class ExceptionResponseStatusHandler {
    @ExceptionHandler(NoHandlerFoundException.class)
    public ModelAndView handle404() {
        var out = new ModelAndView();
        out.setViewName("404");//you must have view named i.e. 404.html
        return out;
    }
}