项目运行时，难免会出现错误，这些错误我们不可以也不方便直接让用户看到，所以配置错误页面是非常必要的。
一下是项目的Web.xml文件，在最下方阴影部分是配置错误界面。
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
version="3.0" metadata-complete="false"> <display-name>esp-web</display-name> <!-- Spring配置文件开始 -->
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>
classpath:spring-common.xml,
classpath:spring-config.xml
</param-value>
</context-param>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<!-- Spring配置文件结束 --> <!-- 可以使用RequestContextHolder.currentRequestAttributes() 获取到请求的attr -->
<listener>
<listener-class>org.springframework.web.context.request.RequestContextListener</listener-class>
</listener> <!-- 设置servlet编码开始 -->
<filter>
<filter-name>Set Character Encoding</filter-name>
<filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
<async-supported>true</async-supported>
<init-param>
<param-name>encoding</param-name>
<param-value>UTF-8</param-value>
</init-param>
<init-param>
<param-name>forceEncoding</param-name>
<param-value>true</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>Set Character Encoding</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<!-- 设置servlet编码结束 --> <!-- 记录访问日志，比如审计之类的可用 -->
<filter>
<filter-name>AccessLogFilter</filter-name>
<filter-class>com.pcitc.common.web.filter.AccessLogFilter</filter-class>
<async-supported>true</async-supported>
<init-param>
<param-name>blackListURL</param-name>
<param-value>/static/**,*.js,*.css,*.jpg,*.gif,*.png,*.ico,/admin/monitor/druid/**</param-value>
</init-param>
<init-param>
<param-name>whiteListURL</param-name>
<param-value>/**</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>AccessLogFilter</filter-name>
<url-pattern>/*</url-pattern>
<dispatcher>REQUEST</dispatcher>
</filter-mapping> <!-- shiro 安全过滤器 -->
<!-- The filter-name matches name of a 'shiroFilter' bean inside applicationContext.xml -->
<filter>
<filter-name>shiroFilter</filter-name>
<filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
<async-supported>true</async-supported>
<init-param>
<param-name>targetFilterLifecycle</param-name>
<param-value>true</param-value>
</init-param>
</filter> <!-- Make sure any request you want accessible to Shiro is filtered. /*
catches all -->
<!-- requests. Usually this filter mapping is defined first (before all
others) to -->
<!-- ensure that Shiro works in subsequent filters in the filter chain: -->
<filter-mapping>
<filter-name>shiroFilter</filter-name>
<url-pattern>/*</url-pattern>
<dispatcher>REQUEST</dispatcher>
</filter-mapping> <!-- 验证码过滤器需要放到Shiro之后 因为Shiro将包装HttpSession 如果不 可能造成两次的sesison id 不一样 -->
<filter>
<filter-name>JCaptchaFilter</filter-name>
<filter-class>com.pcitc.common.web.jcaptcha.JCaptchaFilter</filter-class>
<async-supported>true</async-supported>
</filter>
<filter-mapping>
<filter-name>JCaptchaFilter</filter-name>
<url-pattern>/jcaptcha.jpg</url-pattern>
</filter-mapping> <!--druid 监控 -->
<filter>
<filter-name>DruidWebStatFilter</filter-name>
<filter-class>com.alibaba.druid.support.http.WebStatFilter</filter-class>
<async-supported>true</async-supported>
<init-param>
<param-name>exclusions</param-name>
<param-value>/static/*,*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*</param-value>
</init-param>
<init-param>
<param-name>principalSessionName</param-name>
<param-value>username</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>DruidWebStatFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping> <!-- druid监控 -->
<servlet>
<servlet-name>DruidStatView</servlet-name>
<servlet-class>com.alibaba.druid.support.http.StatViewServlet</servlet-class>
<async-supported>true</async-supported>
</servlet>
<servlet-mapping>
<servlet-name>DruidStatView</servlet-name>
<url-pattern>/admin/monitor/druid/*</url-pattern>
</servlet-mapping> <servlet>
<servlet-name>spring</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:spring-mvc.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
<async-supported>true</async-supported>
</servlet>
<servlet-mapping>
<servlet-name>spring</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
<!-- 自定义tld标签 -->
<jsp-config>
<taglib>
<taglib-uri>http://mytag.sf.net</taglib-uri>
<taglib-location>/WEB-INF/mytag.tld</taglib-location>
</taglib>
</jsp-config> <!-- 错误页面映射 -->
<error-page>
<error-code>404</error-code>
<location>/WEB-INF/jsp/error/error.jsp</location>
</error-page>
<error-page>
<error-code>400</error-code>
<location>/WEB-INF/jsp/error/error.jsp</location>
</error-page>
<error-page>
<error-code>500</error-code>
<location>/WEB-INF/jsp/error/error.jsp</location>
</error-page>
<error-page>
<error-code>503</error-code>
<location>/WEB-INF/jsp/error/error.jsp</location>
</error-page>
<error-page>
<exception-type>java.lang.Exception</exception-type>
<location>/WEB-INF/jsp/error/error.jsp</location>
</error-page> <!--如果 发现报 该错误 No mapping found for HTTP request with URI 加入下mapping <servlet-mapping>
<servlet-name>jsp</servlet-name> <url-pattern>*.jsp</url-pattern> </servlet-mapping --> </web-app>