Spring Framework example source code file (AutowiringTilesRequestProcessor.java)

This example Spring Framework source code file (AutowiringTilesRequestProcessor.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Spring Framework tags/keywords

action, action, actionmapping, autowiringtilesrequestprocessor, configurableapplicationcontext, configurableapplicationcontext, http, illegalstateexception, io, ioexception, moduleconfig, moduleconfig, request, response, servlet, servletexception, tilesrequestprocessor, webapplicationcontext, webapplicationcontext

The Spring Framework AutowiringTilesRequestProcessor.java source code

/*
 * Copyright 2002-2006 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.tiles.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
 */
public class AutowiringTilesRequestProcessor extends TilesRequestProcessor {

	private WebApplicationContext webApplicationContext;

	private int autowireMode = AutowireCapableBeanFactory.AUTOWIRE_NO;

	private boolean dependencyCheck = false;


	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
	 */
	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;
	}

}