WebSpringPentahoObjectFactory.java

/*
 * This program is free software; you can redistribute it and/or modify it under the 
 * terms of the GNU Lesser General Public License, version 2.1 as published by the Free Software 
 * Foundation.
 *
 * You should have received a copy of the GNU Lesser General Public License along with this 
 * program; if not, you can obtain a copy at http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html 
 * or from the Free Software Foundation, Inc., 
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; 
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU Lesser General Public License for more details.
 *
 * Copyright 2008 Pentaho Corporation.  All rights reserved.
 *
 * @created Oct 11, 2008
 * @author Aaron Phillips
 * 
 */
package org.pentaho.platform.web.http.context;

import javax.servlet.ServletContext;

import org.pentaho.platform.engine.core.system.objfac.AbstractSpringPentahoObjectFactory;
import org.pentaho.platform.web.http.messages.Messages;
import org.springframework.web.context.support.WebApplicationContextUtils;

/**
 * This factory implementation can be used in a web environment in which a Spring
 * {@link WebApplicationContext} has already been created during initialization of
 * the web application.  WebSpringPentahoObjectFactory will delegate object creation 
 * and management to the Spring context.  There is one exception to this rule: see 
 * {@link AbstractSpringPentahoObjectFactory} for more details.
 * <p>
 * The Spring bean factory supports the binding of objects to particular scopes.  See Spring
 * documentation for description of the scope types: singleton, prototype, session, and request.
 * The latter two apply only in a web context.
 *
 * @author Aaron Phillips
 * @see AbstractSpringPentahoObjectFactory
 * @see http://static.springframework.org/spring/docs/2.5.x/reference/beans.html#beans-factory-scopes
 */
public class WebSpringPentahoObjectFactory extends AbstractSpringPentahoObjectFactory {

  /**
   * Initializes this object factory by setting the internal bean factory to the {@link WebApplicationContext}
   * instance managed by Spring.
   * 
   * @param configFile  ignored for this implementation
   * @param context   the {@link ServletContext} under which this system is currently running.  This
   *                  is used to retrieve the Spring {@link WebApplicationContext}.
   * @throws IllegalArgumentException if context is not the correct type, only ServletContext is accepted
   */
  public void init(String configFile, Object context) {
    if (!(context instanceof ServletContext)) {
      String msg = Messages.getInstance().getErrorString("WebSpringPentahoObjectFactory.ERROR_0001_CONTEXT_NOT_SUPPORTED", //$NON-NLS-1$
          ServletContext.class.getName(), context.getClass().getName());
      throw new IllegalArgumentException(msg);
    }

    ServletContext servletContext = (ServletContext) context;
    beanFactory = WebApplicationContextUtils.getRequiredWebApplicationContext(servletContext);
  }
}