Spring 中的 404 错误(java config / no web.xml)

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【中文标题】Spring 中的 404 错误(java config / no web.xml)【英文标题】:404 error in Spring (java config / no web.xml) 【发布时间】:2019-07-28 10:32:32 【问题描述】:

尝试在 Web 应用程序中提供自定义 404 错误页面,据我所知,该页面使用 Java Config(因此没有 web.xml)。

我们有以下版本的相关库:spring ("5.1.2.RELEASE")、spring-security ("5.1.1.RELEASE")。

免责声明

我在 *** 中检查了不同的方法。请 不建议 web.xml、Thymeleaf 或 Spring Boot 的结果。这是 不适用。

除其他外;我尝试了以下方法:

@Controller注解(here和here) 添加 web.xml

没有产生预期的结果(即,仍然得到默认的网络服务器布局和错误)。

控制器注解方式

异常包

package ...;

import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.servlet.NoHandlerFoundException;

@ControllerAdvice
public class GlobalExceptionHandler 

    // Option A (used as an alternative to option B)
    //@ExceptionHandler(Exception.class)
    //public String handle(Exception ex) 
    //   return "redirect:/404";
    //

    @RequestMapping(value = "/404", method = RequestMethod.GET)
    public String NotFoundPage() 
        return "404";
    

    // Option B (used as an alternative to option A)
    @ExceptionHandler(Exception.class)
    public ResponseEntity<String> handleNoHandlerFoundException(GlobalExceptionHandler ex) 
        ResponseEntity responseEntity = new ResponseEntity<>(new RestClientException("Testing exception"),
            HttpStatus.NOT_FOUND);
        return responseEntity;
    

初始化类

package ...;

import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
import org.springframework.transaction.annotation.EnableTransactionManagement;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;

import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.http.ResponseEntity;
import org.springframework.http.HttpStatus;
import org.springframework.web.servlet.NoHandlerFoundException;
import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;

@Configuration
@ComponentScan("...")
@EnableWebMvc
@EnableTransactionManagement
@PropertySource("classpath:application.properties")
public class WebAppConfig extends WebMvcConfigurerAdapter 

    @ExceptionHandler( Exception.class )
    public ResponseEntity<RestClientException> handle(NoHandlerFoundException e) 
        return new ResponseEntity<>(new RestClientException("Testing exception"), HttpStatus.NOT_FOUND);
    

    ...

    @Override
    public void addViewControllers(ViewControllerRegistry registry) 
        super.addViewControllers(registry);
        registry.addViewController("/404.jsp").setViewName("404");
    

还有一个Initializer类(public class Initializer implements WebApplicationInitializer),似乎与一些建议的选项冲突(定义here和here);所以 webapp-init 类没有被修改。

web.xml 方法

<?xml version="1.0" encoding="UTF-8"?>
<web-app id="ROOT" xmlns="http://java.sun.com/xml/ns/j2ee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"
    version="2.4">

<error-page>
  <error-code>404</error-code>
  <location>/error</location>
</error-page>
<error-page>
    <exception-type>java.lang.Exception</exception-type>
    <location>/error</location>
</error-page>

</web-app>

已放置 404.jsp404.html 文件(目前在以下所有位置进行测试):

    src/main/resources
    ├── ...
    ├── error
    │   └── 404.html
    ├── public
    │   ├── 404.html
    │   └── error
    │       └── 404.html
    ├── templates
    │   └── 404.html
    └── ...

    src/main/webapp/WEB-INF/
    ├── error.jsp
    ├── tags
    │   └── ...
    └── views
        ├── 404.html
        ├── 404.jsp
        ├── error.jsp
        └── ...

知道什么是缺失或错误吗?

【问题讨论】:

可能已经在 *** 上有了答案,比如***.com/questions/37398385/… 我不这么认为。你用 Spring-Boot 或 Thymeleaf 指向一些东西。那不是我的情况。我添加了一些对我不起作用的建议参考。 尝试遵循相同的文件夹结构。正如那里所说的“如果您想为给定的状态代码显示自定义 HTML 错误页面,您可以将文件添加到 /error 文件夹。”我不会试图变得更聪明,只是做一些有效的事情,然后根据您的需要进行定制。简单 我刚刚尝试过相同的结构(在src/main/resources/public/error/下);还没有运气 找到他们提到 ErrorController 的地方,据我了解,您可以使用自定义错误路径扩展它,或者像他们那样做逻辑。我会在 BasicErrorController 和 AbstractErrorController 中到处放断点,看看流程是什么。 【参考方案1】:

虽然没有我想的那么清楚,但这是一种工作版本,至少可以为错误页面提供一些自定义。这是第一种方法,但希望可以帮助其他人。

处理的异常列表并不广泛,但主要解决 404 错误 (NoHandlerFoundException) 和其他典型 错误,如 InternalServerErrorExceptionNullPointerException,试图在以 Exception 的其他所有内容的一般错误结束。

请注意,这不包括与例如相关的其他例外情况。 JSTL 模板中的语法错误(org.apache.jasper.*;此处显然无法捕获的异常)。

这些是对源代码库的相关更改和添加:

CustomSimpleMappingExceptionResolver.java(提供通用异常,但记录详细信息)

package ...;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Date;
import javax.ws.rs.InternalServerErrorException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.http.HttpStatus;
import org.springframework.web.servlet.handler.SimpleMappingExceptionResolver;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.NoHandlerFoundException;

public class CustomSimpleMappingExceptionResolver extends SimpleMappingExceptionResolver 

    public CustomSimpleMappingExceptionResolver() 
        // Turn logging on by default
        setWarnLogCategory(getClass().getName());
    

    @Override
    public String buildLogMessage(Exception e, HttpServletRequest req) 
        return "MVC exception: " + e.getLocalizedMessage();
    

    @Override
    protected ModelAndView doResolveException(HttpServletRequest request, HttpServletResponse response,
                                              Object handler, Exception ex) 

        // Log exception
        ex.printStackTrace();
        String exceptionCause = ex.toString();
        String exceptionType = ex.getClass().getCanonicalName();

        // Get the ModelAndView to use
        ModelAndView mav = super.doResolveException(request, response, handler, ex);

        // Make more information available to the view - note that SimpleMappingExceptionResolver adds the exception already
        mav.addObject("url", request.getRequestURL());
        mav.addObject("timestamp", new Date());

        ArrayList<String> exceptions404 = new ArrayList<String>(
                Arrays.asList(
                        NoHandlerFoundException.class.getName()
                        )
        );
        ArrayList<String> exceptions500 = new ArrayList<String>(
                Arrays.asList(
                        InternalServerErrorException.class.getName(),
                        NullPointerException.class.getName()
                        )
        );

        String userExceptionDetail = ex.toString();
        String errorHuman = "";
        String errorTech = "";

        if (exceptions404.contains(exceptionType)) 
            errorHuman = "We cannot find the page you are looking for";
            errorTech = "Page not found";
            userExceptionDetail = String.format("The page %s cannot be found", request.getRequestURL());
            mav.setViewName("/error/404");
            mav.addObject("status", HttpStatus.NOT_FOUND.value());
         else if (exceptions500.contains(exceptionType)) 
            errorHuman = "We cannot currently serve the page you request";
            errorTech = "Internal error";
            userExceptionDetail = "The current page refuses to load due to an internal error";
            mav.setViewName("/error/500");
            mav.addObject("status", HttpStatus.INTERNAL_SERVER_ERROR.value());
         else 
            errorHuman = "We cannot serve the current page";
            errorTech = "General error";
            userExceptionDetail = "A generic error prevents from serving the page";
            mav.setViewName("/error/generic");
            mav.addObject("status", response.getStatus());
        

        Exception userException = new Exception(userExceptionDetail);
        mav.addObject("error_human", errorHuman);
        mav.addObject("error_tech", errorTech);
        mav.addObject("exception", userException);
        return mav;
    

WebAppConfig.java(将自定义异常解析器注册为异常处理程序)

package ...;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
import org.springframework.context.annotation.Scope;
import org.springframework.context.annotation.ScopedProxyMode;
import org.springframework.core.env.Environment;
import org.springframework.core.Ordered;
import org.springframework.http.HttpStatus;
import org.springframework.transaction.annotation.EnableTransactionManagement;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
import org.springframework.web.servlet.HandlerExceptionResolver;
import org.springframework.web.servlet.NoHandlerFoundException;
import org.springframework.web.servlet.view.InternalResourceViewResolver;

import java.lang.ClassNotFoundException;
import java.lang.NullPointerException;
import javax.annotation.Resource;
import javax.ws.rs.InternalServerErrorException;
import java.util.Properties;

@Configuration
@ComponentScan("...")
@EnableWebMvc
@EnableTransactionManagement
@PropertySource("classpath:application.properties")
public class WebAppConfig extends WebMvcConfigurerAdapter 

    @Resource
    private Environment env;

    // ...

    @Bean
    HandlerExceptionResolver customExceptionResolver () 
        CustomSimpleMappingExceptionResolver resolver = new CustomSimpleMappingExceptionResolver();
        Properties mappings = new Properties();
        // Mapping Spring internal error NoHandlerFoundException to a view name
        mappings.setProperty(NoHandlerFoundException.class.getName(), "/error/404");
        mappings.setProperty(InternalServerErrorException.class.getName(), "/error/500");
        mappings.setProperty(NullPointerException.class.getName(), "/error/500");
        mappings.setProperty(ClassNotFoundException.class.getName(), "/error/500");
        mappings.setProperty(Exception.class.getName(), "/error/generic");
        resolver.setExceptionMappings(mappings);
        // Set specific HTTP codes
        resolver.addStatusCode("404", HttpStatus.NOT_FOUND.value());
        resolver.addStatusCode("500", HttpStatus.INTERNAL_SERVER_ERROR.value());
        resolver.setDefaultErrorView("/error/generic");
        resolver.setDefaultStatusCode(200);
        // This resolver will be processed before the default ones
        resolver.setOrder(Ordered.HIGHEST_PRECEDENCE);
        resolver.setExceptionAttribute("exception");
        return resolver;
    

    // ...

    @Bean
    public InternalResourceViewResolver setupViewResolver() 
        InternalResourceViewResolver resolver = new InternalResourceViewResolver();
        resolver.setPrefix("/WEB-INF/views");
        resolver.setSuffix(".jsp");
        resolver.setExposeContextBeansAsAttributes(true);
        return resolver;
    

    @Override
    public void addViewControllers(ViewControllerRegistry registry) 
        super.addViewControllers(registry);
    

Initializer.java(添加dispatcherServlet.setThrowExceptionIfNoHandlerFound(true);;可能不需要)

package ...;

import org.springframework.web.WebApplicationInitializer;
import org.springframework.web.context.ContextLoaderListener;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
import org.springframework.web.servlet.DispatcherServlet;

import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRegistration;

public class Initializer implements WebApplicationInitializer 

    public void onStartup(ServletContext servletContext) throws ServletException 
        AnnotationConfigWebApplicationContext ctx = new AnnotationConfigWebApplicationContext();
        ctx.register(WebAppConfig.class);
        servletContext.addListener(new ContextLoaderListener(ctx));
        ctx.setServletContext(servletContext);
        DispatcherServlet dispatcherServlet = new DispatcherServlet(ctx);
        dispatcherServlet.setThrowExceptionIfNoHandlerFound(true);

        // Add the dispatcher servlet mapping manually and make it initialize automatically
        ServletRegistration.Dynamic servlet = servletContext.addServlet("dispatcher", dispatcherServlet);
        servlet.addMapping("/");
        servlet.addMapping("*.png");
        servlet.addMapping("*.jpg");
        servlet.addMapping("*.css");
        servlet.addMapping("*.js");
        servlet.addMapping("*.txt");
        servlet.setLoadOnStartup(1);

        // ...

    

与错误类相关的视图和标签的结构:

    src/main/webapp/WEB-INF/
    ├── tags
    │   └── error.tag
    └── views
        ├── error
        │   ├── 404.jsp
        │   ├── 500.jsp
        └────── generic.jsp

src/main/webapp/WEB-INF/tags/error.tag

<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>

<!DOCTYPE html>
<head>
    <title>Error page</title>
</head>
<body>
<div class="container">
    <h3><c:out value="$error_human" /></h3>

    <p><br/><br/></p>

    <div class="panel panel-primary">
        <div class="panel-heading">
            <c:out value="$error_tech" />
        </div>
        <div class="panel-body">
            <p><c:out value="$exception_message" /></p>
        </div>
    </div>
</div>
</body>
</html>

src/main/webapp/WEB-INF/views/error/404.jsp

<%@ page language="java" contentType="text/html; charset=utf-8"
         pageEncoding="utf-8" isErrorPage="true" %>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<%@ taglib tagdir="/WEB-INF/tags/" prefix="g" %>

<c:set var = "error_human" scope = "session" value = "We cannot find the page you are looking for"/>
<c:set var = "error_tech" scope = "session" value = "Page not found"/>
<c:set var = "exception_message" scope = "session" value = "The current page cannot be found"/>
<g:error />

src/main/webapp/WEB-INF/views/error/500.jsp

<%@ page language="java" contentType="text/html; charset=utf-8"
         pageEncoding="utf-8" isErrorPage="true" %>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<%@ taglib tagdir="/WEB-INF/tags/" prefix="g" %>

<c:set var = "error_human" scope = "session" value = "We cannot currently serve the page you request"/>
<c:set var = "error_tech" scope = "session" value = "Internal error"/>
<c:set var = "exception_message" scope = "session" value = "The current page refuses to load due to an internal error"/>
<g:error />

src/main/webapp/WEB-INF/views/error/generic.jsp

<%@ page language="java" contentType="text/html; charset=utf-8"
         pageEncoding="utf-8" isErrorPage="true" %>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<%@ taglib tagdir="/WEB-INF/tags/" prefix="g" %>

<c:set var = "error_human" scope = "session" value = "We cannot serve the current page"/>
<c:set var = "error_tech" scope = "session" value = "General error"/>
<c:set var = "exception_message" scope = "session" value = "A generic error prevents from serving the page"/>
<g:error />

【讨论】:

【参考方案2】:

阅读 Spring Boot 文档,这对我有用:

  @Bean
   public ErrorPageRegistrar errorPageRegistrar() 
     return registry -> registry.addErrorPages(new ErrorPage(HttpStatus.NOT_FOUND, "/index.html"));  

这相当于 web.xml。

【讨论】:

【参考方案3】:

确保您可以访问 404 页面,然后添加这些代码。

@ControllerAdvice
public class GlobalExceptionHandler 

    @ResponseStatus(HttpStatus.NOT_FOUND)
    @ExceptionHandler(NoHandlerFoundException.class)
    public String handle404(Model model, HttpServletRequest req, Exception ex) 
        return "/404";
    

应用程序.yaml

spring:
  mvc:
    throwExceptionIfNoHandlerFound: true # if page not found, it will throw error, and then ControllerAdvice will catch the error.

PS:springBoot版本=2.4.2; Java=15

【讨论】:

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