<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd" version="4.0"> <!-- 定义上下文参数 --> <context-param> <param-name>appName</param-name> <param-value>MyWebApp</param-value> </context-param> <!-- 定义Servlet --> <servlet> <servlet-name>HelloWorldServlet</servlet-name> <servlet-class>com.example.HelloWorldServlet</servlet-class> <init-param> <param-name>message</param-name> <param-value>Welcome to My Web App!</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <!-- 映射Servlet到URL --> <servlet-mapping> <servlet-name>HelloWorldServlet</servlet-name> <url-pattern>/hello</url-pattern> </servlet-mapping> <!-- 设置欢迎页面 --> <welcome-file-list> <welcome-file>index.html</welcome-file> </welcome-file-list> <!-- 设置错误页面 --> <error-page> <error-code>404</error-code> <location>/error/404.jsp</location> </error-page> <!-- 配置会话超时 --> <session-config> <session-timeout>30</session-timeout> </session-config> </web-app>