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struts2tilesognl

OGNL and wildcards working in tiles definitions with struts2-tiles-plugin?


I want Tiles to resolve ognl from the struts2 value stack. How to do this?

Using tiles 2.2.2 (although if a later version such as 3 could be used that is fine)

Here it mentions the new feature: http://tiles.apache.org/2.2/framework/whats-new.html

Here it shows how to implement it: http://tiles.apache.org/2.2/framework/tutorial/advanced/el-support.html#OGNL_Support

But I'm not certain how to go about that in my project. Does anyone have tiles3 working in their struts2 project? I remember reading about some way to turn on all new features in tiles 3 by default but I can't find a link to that page.

If configuration can be done in anyway with spring that is fine (if that helps, if not it is not an issue).


Solution

  • I love the tiles tempate system because it is simple and straight forward, with Tiles 2.2.2 you can have wild card support to push your struts2 conventions right into the template system and now there is OGNL too!

    Steps to add tiles 2.2.2 with OGNL support within tiles (Currently using Struts 2.3.1.2):

    1) Add the struts2-tiles-plugin

    2) Add the tiles 2.2.2 jars including the jars which add ognl support. Assumes maven: ALL group ids are: org.apache.tiles ALL versions are 2.2.2, the following are artifact ids :

    • tiles-api
    • tiles-core
    • tiles-extras
    • tiles-jsp
    • tiles-ognl
    • tiles-servlet

    Also needed to add the following:

    By using the org.apache.tiles.extras.complete.CompleteAutoloadTilesListener you get Wild Cards, EL, OGNL, MVEL support in your tiles.xml

    Example web.xml:

    <?xml version="1.0" encoding="UTF-8"?>
    <web-app version="2.5" 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_2_5.xsd">
        <listener>
            <listener-class>org.apache.tiles.extras.complete.CompleteAutoloadTilesListener</listener-class>
        </listener>
        <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>
    </web-app>
    

    struts.xml for a demo: The demo uses OGNL from struts to display a hard coded greeting message. Three action mappings exist "", "test", and "package/*" the value that follows the slash will be used by tiles to set a new title. A very trivial example but does show some useful features.

    <struts>
        <constant name="struts.devMode" value="true" />
        <constant name="struts.ui.theme" value="simple" />
        <constant name="struts.enable.SlashesInActionNames" value="true" />
        <constant name="struts.mapper.alwaysSelectFullNamespace" value="false"/>
        <package  name="basicstruts2"  namespace="" extends="tiles-default">
            <result-types>
                <result-type name="tiles" default="true" class="org.apache.struts2.views.tiles.TilesResult"/>
            </result-types>
            <action name="/**" class="com.kenmcwilliams.tiles.action.Test">
                <result>{1}</result>
            </action>
        </package>
    </struts>
    

    tiles.xml

    <?xml version="1.0" encoding="UTF-8"?>
    <!DOCTYPE tiles-definitions PUBLIC
           "-//Apache Software Foundation//DTD Tiles Configuration 2.1//EN"
           "http://tiles.apache.org/dtds/tiles-config_2_1.dtd">
    <tiles-definitions>
        <definition name="baseLayout" template="/WEB-INF/content/tiles/template.jsp">
            <put-attribute name="title" value="Default Title"/>
            <put-attribute name="header" value="/WEB-INF/content/tiles/header.jsp"/>
            <put-attribute name="body" value="/WEB-INF/content/tiles/body.jsp"/>
            <put-attribute name="footer" value="/WEB-INF/content/tiles/footer.jsp"/>
            <put-attribute name="variable"  expression="OGNL:greeting"/>
        </definition>
        <definition name="test" extends="baseLayout">
            <put-attribute name="title" value="Test Title"/>
        </definition>
        <definition name="WILDCARD:package/*" extends="baseLayout">
            <put-attribute name="title" value="{1}" type="string"/>
        </definition>
        <definition name="" extends="baseLayout">
        </definition>
    </tiles-definitions>
    

    /WEB-INF/content/tiles/body.jsp

    <div>
        This is the default body.
    </div>
    

    /WEB-INF/content/tiles/footer.jsp

    <div>
        This is the default footer.
    </div>
    

    /WEB-INF/content/tiles/header.jsp

    <div>
        This is the default header.
    </div>
    

    /WEB-INF/content/tiles/template.jsp

    <%@taglib prefix="tiles" uri="http://tiles.apache.org/tags-tiles" %>
    <%@taglib prefix="s" uri="/struts-tags"%>
    <%@page contentType="text/html" pageEncoding="UTF-8" %>
    <!DOCTYPE html>
    <html>
        <head>
            <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
            <title><tiles:insertAttribute name="title"/></title>
        </head>
        <body>
            <tiles:insertAttribute name="header"/>
            <tiles:insertAttribute name="body"/>
            <tiles:insertAttribute name="footer"/>
            <tiles:insertAttribute name="variable"/>
        </body>
    </html>
    

    Test.java Action

    package com.kenmcwilliams.tiles.action;
    
    import com.opensymphony.xwork2.ActionSupport;
    import java.util.Map;
    import java.util.logging.Logger;
    import org.apache.struts2.interceptor.SessionAware;
    
    public class Test extends ActionSupport implements SessionAware{
        private static final Logger log = Logger.getLogger(Test.class.getName());
        @Override
        public String execute(){
            log.info("Test execute");
            return SUCCESS;
        }
    
        private String greeting = "Hello, World from Action!";
        public String getGreeting(){
            return greeting;
        }
    
        @Override
        public void setSession(Map<String, Object> session) {
            session.put("greeting", "Greetings from session!");
        }
    }
    

    That should now be enough to get tiles working for your application.