URLResourceProvider.java

/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2009, Red Hat Middleware LLC, and individual contributors
 * as indicated by the @author tags. See the copyright.txt file in the
 * distribution for a full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software 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.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package org.jboss.switchboard.mc.resource.provider;

import java.net.MalformedURLException;
import java.net.URL;

import org.jboss.deployers.structure.spi.DeploymentUnit;
import org.jboss.logging.Logger;
import org.jboss.switchboard.impl.resource.IndependentResource;
import org.jboss.switchboard.impl.resource.LinkRefResource;
import org.jboss.switchboard.javaee.environment.ResourceRefType;
import org.jboss.switchboard.javaee.jboss.environment.JBossResourceRefType;
import org.jboss.switchboard.javaee.util.InjectionTargetUtil;
import org.jboss.switchboard.mc.spi.MCBasedResourceProvider;
import org.jboss.switchboard.spi.Resource;

/**
 * URLResourceProvider
 *
 * @author Jaikiran Pai
 * @version $Revision: $
 */
public class URLResourceProvider implements MCBasedResourceProvider<JBossResourceRefType>
{

   private static Logger logger = Logger.getLogger(URLResourceProvider.class);
   
   @Override
   public Class<JBossResourceRefType> getEnvironmentEntryType()
   {
      return JBossResourceRefType.class;
   }

   @Override
   public Resource provide(DeploymentUnit unit, JBossResourceRefType resRef)
   {
      
      String type = this.getResourceRefType(unit.getClassLoader(), resRef);
      if (!URL.class.getName().equals(type))
      {
         return null;
      }
      String url = resRef.getResourceURL();
      if (url != null && !url.trim().isEmpty())
      {
         try
         {
            return new IndependentResource(new URL(url.trim()));
         }
         catch (MalformedURLException murle)
         {
            throw new RuntimeException(murle);
         }
      }
      // fallback on mapped-name
      String mappedName = resRef.getMappedName();
      if (mappedName == null || mappedName.trim().isEmpty())
      {
         throw new RuntimeException("Cannot create a resource out of resource-ref: " + resRef.getName()
               + " because neither non-empty res-url nor non-empty mapped-name is specified");
      }
      try
      {
         URL urlFromMappedName = new URL(mappedName.trim());
         return new IndependentResource(urlFromMappedName);
      }
      catch (MalformedURLException murle)
      {
         // mapped-name is malformed. So cannot be treated as a URL.
         // Treat it as a jndi-name.
         logger.debug("mapped-name " + mappedName + " for URL resource-ref: " + resRef.getName()
               + " is malformed. mapped-name will now be treated as a jndi-name");
         return new LinkRefResource(mappedName.trim());
      }
   }
   
   /**
    * Returns the res-type for the passed {@link ResourceRefType}.
    * <p>
    *   If the passed resource-ref has the res-type explicitly specified, then
    *   that value is returned. Else, this method checks for the presence of any
    *   injection targets for this resource-ref. If there's a injection target, then
    *   the res-type is deduced based on the field/method of the injection target. 
    * </p>
    * <p>
    *   This method returns null if the res-type isn't explicitly specified and 
    *   if the res-type could not be deduced from the injection targets of this
    *   resource-ref.
    * </p>
    * 
    * @param cl The {@link ClassLoader} to be used during processing the metadata
    * @param resourceRef The Java EE resource-ref
    * @return
    */
   private String getResourceRefType(ClassLoader cl, ResourceRefType resourceRef)
   {
      // first check whether the type is explicitly specified
      String explicitType = resourceRef.getResourceType();
      if (explicitType != null && !explicitType.isEmpty())
      {
         return explicitType;
      }
      Class<?> type = InjectionTargetUtil.getInjectionTargetPropertyType(cl, resourceRef);
      return type == null ? null : type.getName();
   }

}