/*

  * This software is licensed under the Apache License, Version 2.0

  * (the "License") agreement; 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 net.admin4j.dao.xml;

 import java.beans.DefaultPersistenceDelegate;

 import java.beans.XMLEncoder;

 import java.io.BufferedOutputStream;

 import java.io.FileOutputStream;

 import java.util.Set;

 import net.admin4j.config.Admin4JConfiguration;

 import net.admin4j.dao.ExceptionInfoDAO;

 import net.admin4j.entity.ExceptionInfo;

 /**

  * DAO implementation for reading and writing Exception information.

  * @author D. Ashmore

  * @since 1.0

  */

 public class ExceptionInfoDAOXml extends BaseDAOXml implements ExceptionInfoDAO {

     private static final Object SAVE_LOCK = new Object();

     @SuppressWarnings("unchecked")

     public Set<ExceptionInfo> findAll() {

         return (Set<ExceptionInfo>) readXmlFile(Admin4JConfiguration.getExceptionInformationXmlFileName());

     }

     public void saveAll(Set<ExceptionInfo> exceptionList) {

         XMLEncoder encoder = null;

         String xmlFileName = Admin4JConfiguration.getExceptionInformationXmlFileName();

         String tempFileName = xmlFileName + ".temp";

         String previousFileName = derivePreviousFileName(xmlFileName);

         boolean encoderClosed = false;

         synchronized (SAVE_LOCK) {

             /*

              * Write to a .temp file

              * Rename configured xml file to .previous

              * Rename new .temp to the configured file name.

              * 

              * Note: classloader assigning business to work around JDK bug

              * http://bugs.sun.com/view_bug.do?bug_id=6329581

              */

             ClassLoader currentContextLoader = Thread.currentThread().getContextClassLoader();

             try {

                 Thread.currentThread().setContextClassLoader(ExceptionInfo.class.getClassLoader());

                 encoder = new XMLEncoder(

                         new BufferedOutputStream(

                             new FileOutputStream(tempFileName)));

                 encoder.setExceptionListener(new DefaultExceptionListener(xmlFileName));

                 encoder.setPersistenceDelegate(ExceptionInfo.class, 

                         new DefaultPersistenceDelegate(

                                 new String[]{"exceptionClassName","stackTrace", "alternateId"}));

                 encoder.setPersistenceDelegate(ExceptionInfo.TimeStamp.class, 

                         new DefaultPersistenceDelegate(

                                 new String[]{"timestampInMillis"}));

                 encoder.setPersistenceDelegate(StackTraceElement.class, 

                         new DefaultPersistenceDelegate(

                                 new String[]{"className","methodName",

                                         "fileName","lineNumber"}));

                 encoder.writeObject(exceptionList);

                 encoder.close();

                 encoderClosed = true;

                 versionOutputFile(xmlFileName, tempFileName, previousFileName);

             }

             catch (Throwable t) {

                 if (encoder != null && !encoderClosed) encoder.close();

             }

             finally {

                 Thread.currentThread().setContextClassLoader(currentContextLoader);

             }

         }

     }

 }