领略下传说中的Struts2，写了个小例子，有点意思。比起.net中的MVC有意思的在于它是你自己一步步去配置实现，想怎么搞就怎么搞，.net的MVC，它干了什么事你完全不知，只不过知道怎么用而已。
下载的struts2版本为2.3，里头有些小例子，我直接使用了最简单的那个struts2-blank.war里的jar包即可。（这是struts2最基本的jar，其实还有一些可以删除的，比如我删除了log4J）
1）有以下有个Jar需要引入到lib文件夹:
asm-3.3.jar asm-commons-3.3.jar asm-tree-3.3.jar commons-fileupload-1.3.1.jar commons-io-2.2.jar commons-lang3-3.1.jar commons-logging-1.1.3.jar freemarker-2.3.19.jar javassist-3.11.0.GA.jar ognl-3.0.6.jar struts2-core-2.3.16.1.jar xwork-core-2.3.16.1.jar
2）建一个BaseActionSupport.java
package com.my.action; import org.apache.struts2.ServletActionContext; import com.opensymphony.xwork2.ActionSupport; /** * Base Action class for the Tutorial package. */ public class BaseActionSupport extends ActionSupport { public String getContextPath() { return ServletActionContext.getRequest().getContextPath(); } }
3）建一个LoginAction.java
package com.my.action; public class LoginAction extends BaseActionSupport { private String userName; private String password; public String getUserName() { return this.userName; } public void setUserName(String userName) { this.userName = userName; } public String getPassword() { return this.password; } public void setPassword(String password) { this.password = password; } public String execute() throws Exception { return INPUT; } public String signin() { if( "admin".equals(getUserName()) && "admin".equals(getPassword()) ) { return SUCCESS; } else { return "false"; } } }
4）建一个MainAction.java
package com.my.action; public class MainAction extends BaseActionSupport { public String execute() throws Exception { return SUCCESS; } }
5）在src目录下建一个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> <constant name="struts.enable.DynamicMethodInvocation" value="false" /> <constant name="struts.devMode" value="true" /> <package name="default" namespace="/" extends="struts-default"> <default-action-ref name="index" /> <global-results> <result name="error">/error.jsp</result> </global-results> <global-exception-mappings> <exception-mapping exception="java.lang.Exception" result="error"/> </global-exception-mappings> </package> <include file="struts_login.xml"/> <!-- Add packages here --> </struts>
6）在src目录下建一个struts_login.xml
<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN" "http://struts.apache.org/dtds/struts-2.0.dtd"> <struts> <package name="login" namespace="/" extends="default"> <action name="login_*" class="com.my.action.LoginAction" method="{1}"> <result type="redirectAction" name="success">main</result> <result type="redirect" name="false">login</result> <result name="input">/pages/Login.jsp</result> </action> <action name="main" class="com.my.action.MainAction"> <result name="success">/pages/Main.jsp</result> </action> <action name="*" class="com.my.action.BaseActionSupport"> <result>/pages/{1}.jsp</result> </action> </package> </struts>
7）建一个jsp：Login.jsp
<%@ page contentType="text/html;charset=utf-8" pageEncoding="utf-8"%> <%@ taglib prefix="s" uri="/struts-tags" %> <html> <head> </head> <body> <form action="login_signin" method="post"> User name:<input type="text" id="userName" name="userName" /><br/> Password:<input type="password" id="password" name="password" /><br/> <input type="submit" value="Login" /> </form> <body> </html>
8）建一个jsp：Main.jsp
<%@ page contentType="text/html;charset=utf-8" pageEncoding="utf-8"%> <%@ taglib prefix="s" uri="/struts-tags" %> <html> <head> </head> <body> This is main page.<br/> Context Path:${contextPath}<br/> Action URL:<s:url action="main"/> <body> </html>
9）修改web.xml
<filter> <filter-name>struts2</filter-name> <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class> </filter> <filter-mapping> <filter-name>struts2</filter-name> <url-pattern>/*</url-pattern> </filter-mapping>
因为没有用eclipse，直接使用命令行javac，写了一个bat做编译：build.bat
@echo off set libDir=D:Studyapache-tomcat-7.0.52webapps estStrutsWEB-INFlib set tempClassPath=%classpath% set classpath=%libDir%asm-3.3.jar;%classpath% set classpath=%libDir%asm-commons-3.3.jar;%classpath% set classpath=%libDir%asm-tree-3.3.jar;%classpath% set classpath=%libDir%commons-fileupload-1.3.1.jar;%classpath% set classpath=%libDir%commons-io-2.2.jar;%classpath% set classpath=%libDir%commons-lang3-3.1.jar;%classpath% set classpath=%libDir%commons-logging-1.1.3.jar;%classpath% set classpath=%libDir%freemarker-2.3.19.jar;%classpath% set classpath=%libDir%javassist-3.11.0.GA.jar;%classpath% set classpath=%libDir%log4j-1.2.17.jar;%classpath% set classpath=%libDir%ognl-3.0.6.jar;%classpath% set classpath=%libDir%struts2-core-2.3.16.1.jar;%classpath% set classpath=%libDir%xwork-core-2.3.16.1.jar;%classpath% @echo on javac -d WEB-INFclasses src*.java @echo off copy src*.xml WEB-INFclasses set classpath=%tempClassPath% @echo on
为了使编译后tomcat自动热加载，在tomcat安装目录下的confserver.xml中加入了这句（在<host/>节点内）：
<Context path="/testStruts" docBase="testStruts" reloadable="true" debug="0"></Context>