/**

  * Copyright 2005-2013 Dozer Project

  *

  * 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.dozer.loader.xml;

 import org.dozer.config.BeanContainer;

 import org.dozer.util.DozerClassLoader;

 import org.dozer.util.DozerConstants;

 import org.slf4j.Logger;

 import org.slf4j.LoggerFactory;

 import org.xml.sax.EntityResolver;

 import org.xml.sax.InputSource;

 import java.io.InputStream;

 import java.net.URL;

 /**

  * Internal EntityResolver implementation to load Xml Schema from the dozer classpath resp. JAR file.

  * 

  * <p>

  * Fetches "beanmapping.xsd" from the classpath resource "/beanmapping.xsd", no matter if specified as some

  * local URL or as "http://dozer.sourceforge.net/schema/beanmapping.xsd".

  * 

  * @author garsombke.franz

  */

 public class DozerResolver implements EntityResolver {

   private final Logger log = LoggerFactory.getLogger(DozerResolver.class);

   public InputSource resolveEntity(String publicId, String systemId) {

     log.debug("Trying to resolve XML entity with public ID [{}] and system ID [{}]", publicId, systemId);

     if (systemId != null && systemId.indexOf(DozerConstants.XSD_NAME) > systemId.lastIndexOf("/")) {

       String fileName = systemId.substring(systemId.indexOf(DozerConstants.XSD_NAME));

       log.debug("Trying to locate [{}] in classpath", fileName);

       try {

         DozerClassLoader classLoader = BeanContainer.getInstance().getClassLoader();

         URL url = classLoader.loadResource(fileName);

         InputStream stream = url.openStream();

         InputSource source = new InputSource(stream);

         source.setPublicId(publicId);

         source.setSystemId(systemId);

         log.debug("Found beanmapping XML Schema [{}] in classpath", systemId);

         return source;

       } catch (Exception ex) {

         log.error("Could not resolve beanmapping XML Schema [" + systemId + "]: not found in classpath", ex);

       }

     }

     // use the default behaviour -> download from website or wherever

     return null;

   }

 }