struts2.0与SiteMesh整合

1.在工程中引入SiteMesh的必要jar包，和struts2-sitemesh-plugin-2.0.8.jar（该包在strut2.0的lib目录中可以找到)；

 

2.Struts2的所有值是保存在Stack Context或者ValueStack中的，默认情况是，
某个过滤器一旦访问了该Stack Context或ValueStack后，里面对应的值将会被清除掉，
如果先使用Struts2的FilterDispatcher来过滤用户请求，
则SiteMesh的过滤器将无法取得Stack Context或者ValueStack中的数据。
为了解决整个问题，Struts2提供了ActionContextCleanUp类。在Struts2的架构中，
标准的过滤器链（filter-chain）一般以 ActionContextCleanUp 开始，后面跟着其他需要的过滤器，
最后，由 FilterDispatcher来处理请求，FilterDispatcher通常是将请求传递给ActionMapper
但问题是：ActionContextCleanUp过滤器只能保证在FilterDispatcher之前先不清除Stack Context和ValueStack中的值。
如果将SiteMesh过滤器排在FilterDispatcher之后，这会导致SiteMesh过滤器无法访问到Stack Context和ValueStack中的值。
因此，为了让SiteMesh过滤器和FilterDispatcher都可访问到Stack Context和ValueStack中的值，
且FilterDispatcher可以在合适时机清除Stack Context和ValueStack中的值，应该使用如下的过滤器顺序：
（1）ActionContextCleanUp过滤器。
（2）SiteMesh核心过滤器。
（3）FilterDispatcher过滤器。

 

3.

  struts2.13前配置如下：

1. filter>  
2.    <filter-name>ActionContextCleanUp</filter-name>  
3.    <filter-class>org.apache.struts2.dispatcher.ActionContextCleanUp</filter-class>  
4. </filter>  
5. <filter>  
6.    <filter-name>sitemesh</filter-name>  
7.    <filter-class>com.opensymphony.module.sitemesh.filter.PageFilter</filter-class>  
8. </filter>  
9. <filter>  
10.    <filter-name>struts2</filter-name>  
11.    <filter-class>org.apache.struts2.dispatcher.FilterDispatcher</filter-class>  
12. </filter>  

 从struts2.1.3开始ActionContextCleanUp 和 FilterDispatcher过滤器，已经不建议使用了。将使用StrutsPrepareFilter 和StrutsExecuteFilter拦截器替代。正确的配置方式如下：

 

<filter>
         <filter-name>struts-prepare</filter-name>
         <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareFilter</filter-class>
     </filter>
     <filter>
         <filter-name>sitemesh</filter-name>
         <filter-class>com.opensymphony.sitemesh.webapp.SiteMeshFilter</filter-class>
     </filter>
     <filter>
         <filter-name>struts-execute</filter-name>
         <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsExecuteFilter</filter-class>
     </filter>

     <filter-mapping>
         <filter-name>struts-prepare</filter-name>
         <url-pattern>/*</url-pattern>
     </filter-mapping>
     <filter-mapping>
         <filter-name>sitemesh</filter-name>
         <url-pattern>/*</url-pattern>
         <dispatcher>REQUEST</dispatcher>
         <dispatcher>FORWARD</dispatcher>
         <dispatcher>INCLUDE</dispatcher>
     </filter-mapping>
     <filter-mapping>
         <filter-name>struts-execute</filter-name>
         <url-pattern>/*</url-pattern>
     </filter-mapping>

     <servlet>
         <servlet-name>sitemesh-freemarker</servlet-name>
         <servlet-class>org.apache.struts2.sitemesh.FreemarkerDecoratorServlet</servlet-class>
         <init-param>
             <param-name>default_encoding</param-name>
             <param-value>UTF-8</param-value>
         </init-param>
         <load-on-startup>1</load-on-startup>
     </servlet>
     <servlet-mapping>
         <servlet-name>sitemesh-freemarker</servlet-name>
         <url-pattern>*.ftl</url-pattern>
     </servlet-mapping>
     <listener>
         <listener-class>org.apache.struts2.dispatcher.ng.listener.StrutsListener</listener-class>
     </listener>

<filter>
		<filter-name>struts-prepare</filter-name>
		<filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareFilter</filter-class>
	</filter>
	<filter>
        <filter-name>sitemesh</filter-name>
        <filter-class>com.opensymphony.sitemesh.webapp.SiteMeshFilter</filter-class>
    </filter>
	<filter>
    	<filter-name>struts-execute</filter-name>
    	<filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsExecuteFilter</filter-class>
	</filter>
	
	<filter-mapping>
		<filter-name>struts-prepare</filter-name>
		<url-pattern>/*</url-pattern>
	</filter-mapping>
	<filter-mapping>
        <filter-name>sitemesh</filter-name>
        <url-pattern>/*</url-pattern>
        <dispatcher>REQUEST</dispatcher>
        <dispatcher>FORWARD</dispatcher>
        <dispatcher>INCLUDE</dispatcher>
    </filter-mapping>
	<filter-mapping>
		<filter-name>struts-execute</filter-name>
		<url-pattern>/*</url-pattern>
	</filter-mapping>
	
	<servlet>
        <servlet-name>sitemesh-freemarker</servlet-name>
        <servlet-class>org.apache.struts2.sitemesh.FreemarkerDecoratorServlet</servlet-class>
        <init-param>
            <param-name>default_encoding</param-name>
            <param-value>UTF-8</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>sitemesh-freemarker</servlet-name>
        <url-pattern>*.ftl</url-pattern>
    </servlet-mapping>
	<listener>
        <listener-class>org.apache.struts2.dispatcher.ng.listener.StrutsListener</listener-class>
    </listener>

    注意：

    1. com.opensymphony.sitemesh.webapp.SiteMeshFilter这个过滤器是必需的，否则装饰不起作用

    2. 为了支持FreeMaker或Velocity，必须添加org.apache.struts2.sitemesh.FreemarkerDecoratorServlet这个Servlet，官方原话：

写道

From 2.2+ the recommended way to use Freemarker with Sitemesh is through the org.apache.struts2.sitemesh.FreemarkerDecoratorServlet servlet

    3. 而已从2.2.x开始，必须添加org.apache.struts2.dispatcher.ng.listener.StrutsListener这个监听器

写道

From 2.2+ the new com.opensymphony.sitemesh.webapp.SiteMeshFilter filter and Struts org.apache.struts2.dispatcher.ng.listener.StrutsListener context listener must be added to web.xml,

 

4.在webroot目錄下面建decorators文件夾,裡面放裝飾的模型main.jsp(decorators是装饰文件默认路径)

<%@ page contentType="text/html;charset=UTF-8"%>
<%@taglib prefix="decorator"
 uri="http://www.opensymphony.com/sitemesh/decorator"%>> //导入sitemesh标签库
<%@taglib prefix="page" uri="http://www.opensymphony.com/sitemesh/page"%<html>
 <head>
  <title><decorator:title /></title>
  <decorator:head />
 </head>
 <body>
  <p>
   Add head decorator...
  </p>
  <decorator:body />
  <p>
   Add foot decorator...
  </p>
 </body>
</html>

 

5.配置decorators-file文件.該文件名称和路径为sitemesh-default.xml中 <property name="decorators-file" value="/WEB-INF/decorators.xml"/>配置的名称.所以该文件必须放在WEB-INF目录下.名称为decorators.xml.

decorators.xml配置如下:

<?xml version="1.0" encoding="utf-8"?>
<decorators defaultdir="/decorators"> //其中/decorators是装饰文件默认路径.也可以配置为其他路径
<!--excludes結點則指定了哪些路徑的請求不使用任何模板-->
<excludes>
<pattern>/index.jsp*</pattern>
<pattern>/login/*</pattern>
</excludes>
<!--decorator結點指定了模板的位置和文件名，通過pattern來指定哪些路徑引用哪個模板-->
<decorator name="main" page="mode.jsp">
<pattern>/*</pattern>
</decorator>
</decorators>