比如一个网上论坛过滤系统，将网友发表的不文明、不和谐的语言，通过拦截器对这些文字进行自动替代。
该项目包含：
1、自定义拦截器(MyInterceptor.java)
2、发表评论的页面(news.jsp)
3、对应的业务控制器(PublicAction.java)
4、业务控制器控制其跳转到success.jsp
代码如下：
1、自定义拦截器(MyInterceptor.java)
package interceptor; import com.opensymphony.xwork2.Action; import com.opensymphony.xwork2.ActionInvocation; import com.opensymphony.xwork2.interceptor.AbstractInterceptor; public class MyInterceptor extends AbstractInterceptor{ public String intercept(ActionInvocation ai) throws Exception { //获取Action的实例 Object object = ai.getAction(); if(object!=null){ if(object instanceof PublicAction){ PublicAction ac=(PublicAction)object; //获取用户提交的评论内容 String content=ac.getContent(); //判断用户提交的评论内容是否有要过滤的内容 if(content.contains("讨厌")){ //以“喜欢”代替要过滤的“讨厌” content = content.replaceAll("讨厌","喜欢"); //把替代后的评论内容设置为Action的评论内容 ac.setContent(content); } //对象不空，继续执行 return ai.invoke(); }else{ //返回Action中的LOGIN逻辑视图字符串 return Action.LOGIN; } } return Action.LOGIN; } }
2、发表评论的页面(news.jsp)
<%@ page language="java" import="java.util.*" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%> <%@ taglib prefix="s" uri="/struts-tags" %> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>Insert title here</title> </head> <body> 请发表你的评论： <hr> <s:form action="public" method="post"> <s:textfield name="title" label="评论标题" maxLength="36" /> <s:textarea name="content" rows="6" cols="36" label="评论内容" /> <s:submit value="提交" /> </s:form> </body> </html>
3、对应的业务控制器(PublicAction.java)
package interceptor; import com.opensymphony.xwork2.ActionSupport; public class PublicAction extends ActionSupport{ private String title; private String content; public String getTitle() { return title; } public void setTitle(String title) { this.title = title; } public String getContent() { return content; } public void setContent(String content) { this.content = content; } public String execute() throws Exception{ return "success"; } }
4、业务控制器控制其跳转到success.jsp
<%@ page language="java" import="java.util.*" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%> <%@ taglib prefix="s" uri="/struts-tags" %> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>Insert title here</title> </head> <body> 评论如下： <hr> 评论标题：<s:property value="title" /> <br> 评论内容：<s:property value="content" /> </body> </html>
5、struts.xml
<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN" "http://struts.apache.org/dtds/struts-2.3.dtd"> <struts> <package name="intercept" extends="struts-default"> <interceptors> <interceptor name="replace" class="interceptor.MyInterceptor" ></interceptor> </interceptors> <action name="public" class="interceptor.PublicAction"> <result name="success">/success.jsp</result> <result name="login">/success.jsp</result> <interceptor-ref name="defaultStack"></interceptor-ref> <interceptor-ref name="replace"></interceptor-ref> </action> </package> </struts>
6、web.xml
<?xml version="1.0" encoding="UTF-8"?> <web-app version="2.4" 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"> <filter> <!-- 配置Struts2核心Filter的名字 --> <filter-name>struts2</filter-name> <!-- 配置Struts2核心Filter的实现类 --> <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class> </filter> <!-- 配置Filter拦截的URL --> <filter-mapping> <!-- 配置Struts2的核心FilterDispatcher拦截所有用户请求 --> <filter-name>struts2</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list> </web-app>