/*

  * Copyright 2006-2011 The Kuali Foundation

  *

  * Licensed under the Educational Community 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.opensource.org/licenses/ecl2.php

  *

  * 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.kuali.rice.core.impl.resourceloader;

 import org.apache.commons.lang.StringUtils;

 import org.kuali.rice.core.api.config.property.ConfigContext;

 import org.kuali.rice.core.api.reflect.ObjectDefinition;

 import org.kuali.rice.core.api.resourceloader.ServiceLocator;

 import org.kuali.rice.core.api.util.ClassLoaderUtils;

 import org.kuali.rice.core.api.util.RiceConstants;

 import org.kuali.rice.core.framework.resourceloader.BaseResourceLoader;

 import javax.xml.namespace.QName;

 import java.util.Collections;

 import java.util.HashMap;

 import java.util.HashSet;

 import java.util.Map;

 import java.util.Set;

 /**

  * A BaseResourceLoader implementation which wraps services with a Proxy that

  * switches the current context ClassLoader of the Thread.

  *

  * @author Kuali Rice Team (rice.collab@kuali.org)

  */

 public class BaseWrappingResourceLoader extends BaseResourceLoader {

         private static final String[] PACKAGES_TO_FILTER = new String[] { "org.springframework" };

         private Set<QName> servicesToCache = new HashSet<QName>();

         private Map<QName, Object> serviceCache = Collections.synchronizedMap(new HashMap<QName, Object>());

         public BaseWrappingResourceLoader(QName name, ClassLoader classLoader, ServiceLocator serviceLocator) {

                 super(name, classLoader, serviceLocator);

         }

         public BaseWrappingResourceLoader(QName name, ClassLoader classLoader) {

                 super(name, classLoader);

         }

         public BaseWrappingResourceLoader(QName name, ServiceLocator serviceLocator) {

                 super(name, serviceLocator);

         }

         public BaseWrappingResourceLoader(QName name) {

                 super(name);

         }

         @Override

         public void start() throws Exception {

             String servicesToCacheFromConfig = ConfigContext.getCurrentContextConfig().getProperty(RiceConstants.SERVICES_TO_CACHE);

             if (!StringUtils.isEmpty(servicesToCacheFromConfig)) {

                 String[] services = servicesToCacheFromConfig.split(",");

                 for (String serviceName : services) {

                     serviceName = serviceName.trim();

                     try {

                         servicesToCache.add(QName.valueOf(serviceName));

                         LOG.info("Adding service " + serviceName + " to service cache.");

                     } catch (IllegalArgumentException e) {

                         LOG.error("Failed to parse serviceName into QName from property " + RiceConstants.SERVICES_TO_CACHE +".  Service name given was: " + serviceName);

                     }

                 }

             }

             super.start();

         }

         @Override

         public Object getService(QName serviceName) {

             Object service = serviceCache.get(serviceName);

             if (service != null) {

                 if (LOG.isDebugEnabled()) {

                     LOG.debug("Service with QName " + serviceName + " was retrieved from the service cache.");

                 }

                 return service;

             }

             return super.getService(serviceName);

         }

         protected Object postProcessService(QName serviceName, Object service) {

                 if (service != null && shouldWrapService(serviceName, service)) {

                         service = ContextClassLoaderProxy.wrap(service, ClassLoaderUtils.getInterfacesToProxy(service, getClassLoader(), getPackageNamesToFilter()), getClassLoader());

                 }

                 cacheService(serviceName, service);

                 return service;

         }

         protected Object postProcessObject(ObjectDefinition definition, Object object) {

                 if (object != null && shouldWrapObject(definition, object)) {

                         return ContextClassLoaderProxy.wrap(object, ClassLoaderUtils.getInterfacesToProxy(object, getClassLoader(), getPackageNamesToFilter()), getClassLoader(), getClassLoader());

                 }

                 return object;

         }

         protected void cacheService(QName serviceName, Object service) {

             if (shouldCacheService(serviceName, service)) {

                 LOG.debug("Adding service " + serviceName + " to the service cache.");

                 serviceCache.put(serviceName, service);

             }

         }

         protected String[] getPackageNamesToFilter() {

                 return PACKAGES_TO_FILTER;

         }

         protected boolean shouldWrapService(QName serviceName, Object service) {

                 return true;

         }

         protected boolean shouldCacheService(QName serviceName, Object service) {

             return servicesToCache.contains(serviceName);

         }

         protected boolean shouldWrapObject(ObjectDefinition definition, Object object) {

                 return true;

         }

 }