Alternative to org.apache.struts.tiles2.RedeployableActionServlet?

[tdferreira]

Hello everyone, it's great to see that some people are actively working on getting Struts up to date. It's certainly important for old projects that for various reason don't want to migrate the tech stack.

I'm not sure this is the right place to ask this, but I see that org.apache.struts.tiles2.RedeployableActionServlet has been removed in v1.4.1, is there a reason for this?
org.apache.struts.tiles.RedeployableActionServlet still exists though.

As I don't see anything documented about this, can you clarify what's the alternative servlet-class to add in the web.xml for tiles2?

thank you

[ste-gr]

Hi @tdferreira,

I've removed org.apache.struts.tiles.RedeployableActionServlet with commit 3ca50c6.
The reason was that I was not able (due to lake of time) to keep this functionality when upgrading from Tiles 2.x to Tiles 3.x. But perhaps this class is not longer necessary these days. It seems that this class tries to do a workaround when redeploying the web-app under WebLogic 6/7 (about 2003), see also STR-1937 - WebLogic hot-deploy breaks Tiles.

But after a little analysis of Tile 3.x it looks like this functionality of refreshing outdated configuration is done by itself. So I think the org.apache.struts.tiles.RedeployableActionServlet and org.apache.struts.tiles.actions.ReloadDefinitionsAction are no longer needed.

If you have a running example, it would be nice to add it to the example-apps.

I haven't spend much time in Struts-Tile2 as it was a new lib in the current apache-struts-trunk branch and wasn't released before weblegacy-struts1.

I hope I could help you a little
Greetings
Stefan

[tdferreira]

I'm a bit confused.
That means that on your project we should use struts-tiles, which you've worked on integrating with Tiles 3.x, and just ignore struts-tiles2? Or is struts-tiles2 working fine with Tiles 3.x?
So we could possibly still use org.apache.struts.tiles.RedeployableActionServlet in the web.xml? or eventually just directly add the listener-class org.apache.tiles.extras.complete.CompleteAutoloadTilesListener from Tiles 3.x.

Have you done any rebase with the latest code from https://github.com/apache/struts1?

[ste-gr]

Hi @tdferreira,

no struts-tiles (weblegacy) is like the struts-tiles from Apache-Struts 1.3.10.
And the basis of struts-tiles2 (weblegacy) is that of struts-tiles2 from Apache-Struts 1.4.0-SNAPSHOT (trunk version).

And with the commit 3ca50c6 I tried to upgrade the Tiles dependency in struts-tiles2 (weblegacy) from 2.x to 3.x. So yes, it was the goal to make struts-tile2 works fine with Tiles 3.x 😉. But I don't have a project to test that. Do you use struts-tiles2 in your projects and can you test it and maybe improve it?

Rebase from Apache-Struts1: The WebLegacy-Struts1 version 1.4.0 is based on Apache-Struts 1.4.0-SNAPSHOT (trunk version).

Greetings
Stefan

[tdferreira]

Just to share a bit of my experience with this.
I have a project still using Struts1 and Tiles1, it also uses Spring MVC 3.
I'm upgrading it to SpringMVC 5, Tiles3 and Struts 1.4.5.
Running the project on Weblogic 12.2.1.4.
I've encountered some issues.

I'm using these maven dependencies:

	<properties>
		<spring.version>5.3.33</spring.version>
		<tiles.version>3.0.8</tiles.version>
	</properties>

	<dependencies>
		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-web</artifactId>
			<version>${spring.version}</version>
		</dependency>
		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-context</artifactId>
			<version>${spring.version}</version>
		</dependency>
		<dependency>
			<groupId>org.springframework</groupId>
			<artifactId>spring-webmvc</artifactId>
			<version>${spring.version}</version>
		</dependency>
		<dependency>
			<groupId>org.apache.tiles</groupId>
			<artifactId>tiles-compat</artifactId>
			<version>${tiles.version}</version>
		</dependency>
		<dependency>
			<groupId>org.apache.tiles</groupId>
			<artifactId>tiles-api</artifactId>
			<version>${tiles.version}</version>
		</dependency>
		<dependency>
			<groupId>org.apache.tiles</groupId>
			<artifactId>tiles-core</artifactId>
			<version>${tiles.version}</version>
		</dependency>
		<dependency>
			<groupId>org.apache.tiles</groupId>
			<artifactId>tiles-servlet</artifactId>
			<version>${tiles.version}</version>
		</dependency>
		<dependency>
			<groupId>org.apache.tiles</groupId>
			<artifactId>tiles-jsp</artifactId>
			<version>${tiles.version}</version>
		</dependency>
		<dependency>
			<groupId>org.apache.tiles</groupId>
			<artifactId>tiles-el</artifactId>
			<version>${tiles.version}</version>
		</dependency>
		<dependency>
			<groupId>org.apache.tiles</groupId>
			<artifactId>tiles-extras</artifactId>
			<version>${tiles.version}</version>
		</dependency>

		<dependency>
			<groupId>io.github.weblegacy</groupId>
			<artifactId>struts-core</artifactId>
			<version>${struts.version}</version>
			<exclusions>
				<exclusion>
					<groupId>commons-logging</groupId>
					<artifactId>commons-logging</artifactId>
				</exclusion>
			</exclusions>
		</dependency>
		<dependency>
			<groupId>io.github.weblegacy</groupId>
			<artifactId>struts-extras</artifactId>
			<version>${struts.version}</version>
			<exclusions>
				<exclusion>
					<groupId>commons-logging</groupId>
					<artifactId>commons-logging</artifactId>
				</exclusion>
			</exclusions>
		</dependency>
    <dependency>
      <groupId>io.github.weblegacy</groupId>
      <artifactId>struts-tiles</artifactId>
      <version>${struts.version}</version>
      <exclusions>
        <exclusion>
          <groupId>commons-logging</groupId>
          <artifactId>commons-logging</artifactId>
        </exclusion>
      </exclusions>
    </dependency>
		<dependency>
			<groupId>io.github.weblegacy</groupId>
			<artifactId>struts-tiles2</artifactId>
			<version>${struts.version}</version>
			<exclusions>
				<exclusion>
					<groupId>commons-logging</groupId>
					<artifactId>commons-logging</artifactId>
				</exclusion>
				<!--
                 | Excludes older version (in apache pom)
                 -->
				<!--<exclusion>
					<groupId>org.apache.tiles</groupId>
					<artifactId>tiles-api</artifactId>
				</exclusion>
				<exclusion>
					<groupId>org.apache.tiles</groupId>
					<artifactId>tiles-core</artifactId>
				</exclusion>-->
			</exclusions>
		</dependency>
		<dependency>
			<groupId>io.github.weblegacy</groupId>
			<artifactId>struts-taglib</artifactId>
			<version>${struts.version}</version>
			<exclusions>
				<exclusion>
					<groupId>commons-logging</groupId>
					<artifactId>commons-logging</artifactId>
				</exclusion>
			</exclusions>
		</dependency>

On my struts-config.xml I have:

  <plug-in className="org.apache.struts.tiles2.TilesPlugin">
    <set-property property="definitions-config" value="/WEB-INF/tiles-defs.xml"/>
    <set-property property="moduleAware" value="true"/>
    <set-property property="definitions-parser-validate" value="true"/>
  </plug-in>

On the web.xml I have:

  <servlet>
    <servlet-name>action</servlet-name>
    <servlet-class>org.apache.struts.action.ActionServlet</servlet-class>
    <init-param>
      <param-name>definitions-debug</param-name>
      <param-value>0</param-value>
    </init-param>
    <init-param>
      <param-name>definitions-parser-details</param-name>
      <param-value>false</param-value>
    </init-param>
    <init-param>
      <param-name>definitions-parser-validate</param-name>
      <param-value>true</param-value>
    </init-param>
    <init-param>
      <param-name>config</param-name>
      <param-value>
        /WEB-INF/struts-config.xml
      </param-value>
    </init-param>
    <init-param>
      <param-name>detail</param-name>
      <param-value>0</param-value>
    </init-param>
    <init-param>
      <param-name>validate</param-name>
      <param-value>true</param-value>
    </init-param>
    <init-param>
      <param-name>convertNull</param-name>
      <param-value>true</param-value>
    </init-param>
    <load-on-startup>2</load-on-startup>
  </servlet>

And it simply doesn't work.

Tried to use the org.apache.tiles.web.startup.simple.SimpleTilesListener and org.apache.tiles.extras.complete.CompleteAutoloadTilesListener in the web.xml, and had NullPointerException.

<listener>
    <listener-class>org.apache.tiles.extras.complete.CompleteAutoloadTilesListener</listener-class>
  </listener> 

Tried also to use the old Spring3 AutowiringTilesRequestProcessor controller in the struts-config.xml, which also didn't work.

<controller
    processorClass="org.springframework.web.struts.AutowiringTilesRequestProcessor"
    contentType="text/html; charset=UTF-8"
    nocache="true"/>

The AutowiringTilesRequestProcessor.java class looks like:

/*
 * Copyright 2002-2012 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.web.struts;

import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.struts.action.Action;
import org.apache.struts.action.ActionMapping;
import org.apache.struts.action.ActionServlet;
import org.apache.struts.config.ModuleConfig;


import org.apache.struts.tiles2.TilesRequestProcessor;
import org.springframework.beans.factory.config.AutowireCapableBeanFactory;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.web.context.WebApplicationContext;

/**
 * Subclass of Struts's TilesRequestProcessor that autowires Struts Actions
 * with Spring beans defined in ContextLoaderPlugIn's WebApplicationContext
 * or - in case of general service layer beans - in the root WebApplicationContext.
 *
 * <p>Behaves like
 * {@link AutowiringRequestProcessor AutowiringRequestProcessor},
 * but also provides the Tiles functionality of the original TilesRequestProcessor.
 * As there's just a single central class to customize in Struts, we have to provide
 * another subclass here, covering both the Tiles and the Spring delegation aspect.
 *
 * <p>The default implementation delegates to the DelegatingActionUtils
 * class as fas as possible, to reuse as much code as possible despite
 * the need to provide two RequestProcessor subclasses. If you need to
 * subclass yet another RequestProcessor, take this class as a template,
 * delegating to DelegatingActionUtils just like it.
 *
 * @author Juergen Hoeller
 * @since 2.0
 * @see AutowiringRequestProcessor
 * @see ContextLoaderPlugIn
 * @see DelegatingActionUtils
 * @deprecated as of Spring 3.0
 */
@Deprecated
public class AutowiringTilesRequestProcessor extends TilesRequestProcessor {

	private WebApplicationContext webApplicationContext;

	private int autowireMode = AutowireCapableBeanFactory.AUTOWIRE_NO;

	private boolean dependencyCheck = false;


	@Override
	public void init(ActionServlet actionServlet, ModuleConfig moduleConfig) throws ServletException {
		super.init(actionServlet, moduleConfig);
		if (actionServlet != null) {
			this.webApplicationContext = initWebApplicationContext(actionServlet, moduleConfig);
			this.autowireMode = initAutowireMode(actionServlet, moduleConfig);
			this.dependencyCheck = initDependencyCheck(actionServlet, moduleConfig);
		}
	}

	/**
	 * Fetch ContextLoaderPlugIn's WebApplicationContext from the ServletContext,
	 * falling back to the root WebApplicationContext. This context is supposed
	 * to contain the service layer beans to wire the Struts Actions with.
	 * @param actionServlet the associated ActionServlet
	 * @param moduleConfig the associated ModuleConfig
	 * @return the WebApplicationContext
	 * @throws IllegalStateException if no WebApplicationContext could be found
	 * @see DelegatingActionUtils#findRequiredWebApplicationContext
	 * @see ContextLoaderPlugIn#SERVLET_CONTEXT_PREFIX
	 */
	protected WebApplicationContext initWebApplicationContext(
			ActionServlet actionServlet, ModuleConfig moduleConfig) throws IllegalStateException {

		WebApplicationContext wac =
				DelegatingActionUtils.findRequiredWebApplicationContext(actionServlet, moduleConfig);
		if (wac instanceof ConfigurableApplicationContext) {
			((ConfigurableApplicationContext) wac).getBeanFactory().ignoreDependencyType(ActionServlet.class);
		}
		return wac;
	}

	/**
	 * Determine the autowire mode to use for wiring Struts Actions.
	 * <p>The default implementation checks the "autowire" init-param of the
	 * Struts ActionServlet, falling back to "AUTOWIRE_BY_TYPE" as default.
	 * @param actionServlet the associated ActionServlet
	 * @param moduleConfig the associated ModuleConfig
	 * @return the autowire mode to use
	 * @see DelegatingActionUtils#getAutowireMode
	 * @see org.springframework.beans.factory.config.AutowireCapableBeanFactory#autowireBeanProperties
	 * @see org.springframework.beans.factory.config.AutowireCapableBeanFactory#AUTOWIRE_BY_TYPE
	 * @see org.springframework.beans.factory.config.AutowireCapableBeanFactory#AUTOWIRE_BY_NAME
	 */
	protected int initAutowireMode(ActionServlet actionServlet, ModuleConfig moduleConfig) {
		return DelegatingActionUtils.getAutowireMode(actionServlet);
	}

	/**
	 * Determine whether to apply a dependency check after wiring Struts Actions.
	 * <p>The default implementation checks the "dependencyCheck" init-param of the
	 * Struts ActionServlet, falling back to no dependency check as default.
	 * @param actionServlet the associated ActionServlet
	 * @param moduleConfig the associated ModuleConfig
	 * @return whether to enforce a dependency check or not
	 * @see DelegatingActionUtils#getDependencyCheck
	 * @see org.springframework.beans.factory.config.AutowireCapableBeanFactory#autowireBeanProperties
	 */
	protected boolean initDependencyCheck(ActionServlet actionServlet, ModuleConfig moduleConfig) {
		return DelegatingActionUtils.getDependencyCheck(actionServlet);
	}


	/**
	 * Return the current Spring WebApplicationContext.
	 */
	protected final WebApplicationContext getWebApplicationContext() {
		return this.webApplicationContext;
	}

	/**
	 * Return the autowire mode to use for wiring Struts Actions.
	 */
	protected final int getAutowireMode() {
		return autowireMode;
	}

	/**
	 * Return whether to apply a dependency check after wiring Struts Actions.
	 */
	protected final boolean getDependencyCheck() {
		return dependencyCheck;
	}


	/**
	 * Extend the base class method to autowire each created Action instance.
	 * @see org.springframework.beans.factory.config.AutowireCapableBeanFactory#autowireBeanProperties
	 */
	@Override
	protected Action processActionCreate(
			HttpServletRequest request, HttpServletResponse response, ActionMapping mapping)
			throws IOException {

		Action action = super.processActionCreate(request, response, mapping);
		getWebApplicationContext().getAutowireCapableBeanFactory().autowireBeanProperties(
				action, getAutowireMode(), getDependencyCheck());
		return action;
	}

}

So I thought of having Spring initializing Tiles, by using the Spring Configuration.

package org.myproject.common.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.accept.ContentNegotiationManager;
import org.springframework.web.servlet.View;
import org.springframework.web.servlet.ViewResolver;
import org.springframework.web.servlet.view.ContentNegotiatingViewResolver;
import org.springframework.web.servlet.view.UrlBasedViewResolver;
import org.springframework.web.servlet.view.json.MappingJackson2JsonView;
import org.springframework.web.servlet.view.tiles3.SpringBeanPreparerFactory;
import org.springframework.web.servlet.view.tiles3.TilesConfigurer;
import org.springframework.web.servlet.view.tiles3.TilesView;

import java.util.ArrayList;
import java.util.List;
import java.util.Locale;

@Configuration
public class SpringMvcStrutsConfig {
    private static final long serialVersionUID = 202231381636L;

    @Bean
    public ViewResolver contentNegotiatingViewResolver(ContentNegotiationManager manager) {
        List<ViewResolver> resolvers = new ArrayList<>();

        resolvers.add(tilesViewResolver());
        JsonViewResolver r2 = new JsonViewResolver();
        resolvers.add(r2);

        // Create the CNVR plugging in the resolvers and the content-negotiation manager
        ContentNegotiatingViewResolver resolver = new ContentNegotiatingViewResolver();
        resolver.setViewResolvers(resolvers);
        resolver.setContentNegotiationManager(manager);
        return resolver;
    }

    @Bean
    public UrlBasedViewResolver tilesViewResolver() {
        UrlBasedViewResolver resolver = new UrlBasedViewResolver();
        //<property name="viewClass" value="org.springframework.web.servlet.view.tiles.TilesJstlView" />
        resolver.setViewClass(TilesView.class);
        return resolver;
    }

    @Bean
    public TilesConfigurer tilesConfigurer() {
        TilesConfigurer ret = new TilesConfigurer();
        ret.setDefinitions("/WEB-INF/tiles-defs.xml");
        ret.setUseMutableTilesContainer(true);
        ret.setPreparerFactoryClass(SpringBeanPreparerFactory.class);
        return ret;
    }

    /**
     * View resolver for returning JSON in a view-based system. Always returns a
     * {@link MappingJackson2JsonView}.
     */
    public class JsonViewResolver implements ViewResolver {
        public View resolveViewName(String viewName, Locale locale) throws Exception {
            MappingJackson2JsonView view = new MappingJackson2JsonView();
            view.setPrettyPrint(true);
            return view;
        }
    }
}

Obviously you'll need also to set the Spring @ComponentScan, @EnableWebMvc, etc., but finally with this it worked. Certainly Spring did its magic! :)