/**

  * Copyright 2005-2011 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.kew.validation;

 import org.apache.commons.lang.StringUtils;

 import org.apache.log4j.Logger;

 import org.kuali.rice.core.api.exception.RiceIllegalArgumentException;

 import org.kuali.rice.kew.api.extension.ExtensionDefinition;

 import org.kuali.rice.kew.api.extension.ExtensionRepositoryService;

 import org.kuali.rice.kew.api.extension.ExtensionUtils;

 import org.kuali.rice.kew.api.validation.RuleValidationContext;

 import org.kuali.rice.kew.api.validation.ValidationResults;

 import org.kuali.rice.kew.framework.validation.RuleValidationAttributeExporterService;

 import org.kuali.rice.kew.rule.RuleValidationAttribute;

 import org.springframework.beans.factory.annotation.Required;

 /**

  * RuleValidationAttributeExporterService reference impl.  Delegates to the ExtensionRepositoryService

  * to load the custom RuleValidationAttribute.

  *

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

  */

 public class RuleValidationAttributeExporterServiceImpl implements RuleValidationAttributeExporterService {

     private static final Logger LOG = Logger.getLogger(RuleValidationAttributeExporterServiceImpl.class);

     private ExtensionRepositoryService extensionRepositoryService;

     @Required

     public void setExtensionRepositoryService(ExtensionRepositoryService extensionRepositoryService) {

         this.extensionRepositoryService = extensionRepositoryService;

     }

     private ExtensionRepositoryService getExtensionRepositoryService() {

         return this.extensionRepositoryService;

     }

     @Override

     public ValidationResults validate(String attributeName, RuleValidationContext validationContext) {

         if (StringUtils.isBlank(attributeName)) {

             throw new RiceIllegalArgumentException("attribute name was null or blank");

         }

         RuleValidationAttribute attr = loadAttribute(attributeName);

         return attr.validate(validationContext);

     }

     /**

      * Loads RuleValidationAttribute implementation class via {@link ExtensionRepositoryService}

      * @param attributeName the RuleValidationAttribute name

      * @return instance of the RuleValidationAttribute implementation class

      * @throws RiceIllegalArgumentException if specified attribute name cannot be found or loaded

      */

     protected RuleValidationAttribute loadAttribute(String attributeName) {

         ExtensionDefinition extensionDefinition = getExtensionRepositoryService().getExtensionByName(attributeName);

         if (extensionDefinition == null) {

             throw new RiceIllegalArgumentException("Failed to locate a RuleValidationAttribute with the given name: " + attributeName);

         }

         RuleValidationAttribute attribute = ExtensionUtils.loadExtension(extensionDefinition);

         if (attribute == null) {

             throw new RiceIllegalArgumentException("Failed to load RuleValidationAttribute for: " + extensionDefinition);

         }

         return attribute;

     }

 }