Glassfish example source code file (PersistenceXMLReaderWriter.java)

This example Glassfish source code file (PersistenceXMLReaderWriter.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Glassfish tags/keywords

classloader, io, ioexception, ioexception, jaxbcontext, jaxbcontext, jaxbexception, jaxbexception, log, logging, marshaller, net, network, outputstream, persistence, persistence, thread, unmarshaller, writer

The Glassfish PersistenceXMLReaderWriter.java source code

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright (c) 2009-2010 Oracle and/or its affiliates. All rights reserved.
 *
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
 * or packager/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 *
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at packager/legal/LICENSE.txt.
 *
 * GPL Classpath Exception:
 * Oracle designates this particular file as subject to the "Classpath"
 * exception as provided by Oracle in the GPL Version 2 section of the License
 * file that accompanied this code.
 *
 * Modifications:
 * If applicable, add the following below the License Header, with the fields
 * enclosed by brackets [] replaced by your own identifying information:
 * "Portions Copyright [year] [name of copyright owner]"
 *
 * Contributor(s):
 * If you wish your version of this file to be governed by only the CDDL or
 * only the GPL Version 2, indicate your decision by adding "[Contributor]
 * elects to include this software in this distribution under the [CDDL or GPL
 * Version 2] license."  If you don't indicate a single choice of license, a
 * recipient has the option to distribute your version of this file under
 * either the CDDL, the GPL Version 2 or to extend the choice of license to
 * its licensees as provided above.  However, if you add GPL Version 2 code
 * and therefore, elected the GPL Version 2 license, then the option applies
 * only if the new code is made subject to such option by the copyright
 * holder.
 */

package org.glassfish.osgijpa.dd;

import org.glassfish.internal.api.Globals;
import org.glassfish.internal.api.ClassLoaderHierarchy;

import javax.xml.bind.Marshaller;
import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Unmarshaller;
import java.io.InputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.Writer;
import java.net.URL;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 * @author Sanjeeb.Sahoo@Sun.COM
 */
public class PersistenceXMLReaderWriter
{
    private static final Logger logger = Logger.getLogger(
            PersistenceXMLReaderWriter.class.getPackage().getName());

    public Persistence read(URL pxmlURL) throws IOException
    {
        InputStream is = pxmlURL.openStream();
        try {
            return read(is);
        } finally {
            is.close();
        }
    }

    public Persistence read(InputStream is) throws IOException {
        try {
            Unmarshaller unmarshaller = getUnmarshaller();
            return (Persistence) unmarshaller.unmarshal(is);
        } catch (JAXBException je) {
            je.printStackTrace();
            IOException ioe = new IOException();
            ioe.initCause(je);
            throw ioe;
        }
    }

    public void write(Persistence persistence, OutputStream os)
            throws IOException {
        try {
            getMarshaller(persistence.getClass()).marshal(persistence,
                    os);
        } catch (JAXBException je) {
            je.printStackTrace();
            IOException ioe = new IOException();
            ioe.initCause(je);
            throw ioe;
        }
    }

    public void write(Persistence persistence, Writer writer)
            throws IOException {
        try {
            getMarshaller(persistence.getClass()).marshal(persistence,
                    writer);
        } catch (JAXBException je) {
            je.printStackTrace();
            IOException ioe = new IOException();
            ioe.initCause(je);
            throw ioe;
        }
    }

    private Marshaller getMarshaller(Class<?> clazz) throws JAXBException {
         JAXBContext jc = getJAXBContext();
         Marshaller marshaller = jc.createMarshaller();
         marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT,
                 Boolean.TRUE);
         return marshaller;
     }

    private Unmarshaller getUnmarshaller() throws JAXBException {
        JAXBContext jc = getJAXBContext();
        return jc.createUnmarshaller();
    }

    private JAXBContext getJAXBContext() throws JAXBException {
        // We need to set context class loader to be CommonClassLoader, otherwise our stupid JAXB implementation
        // won't be able to locate the default JAXB context factory class.
        final Thread thread = Thread.currentThread();
        ClassLoader oldCL = thread.getContextClassLoader();
        try {
            ClassLoader ccl = Globals.get(ClassLoaderHierarchy.class).getCommonClassLoader();
            thread.setContextClassLoader(ccl);
            JAXBContext jc = JAXBContext.newInstance(ObjectFactory.class);
        return jc;
        } finally {
            thread.setContextClassLoader(oldCL);
        }
    }

}