/**
* Copyright (C) 2010 eXo Platform SAS.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.xcmis.spi;
import org.xcmis.spi.utils.Logger;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.nio.charset.Charset;
/**
* Find implementation of CmisRegistryFactory Class.
*
* @author <a href="mailto:andrew00x@gmail.com">Andrey Parfonov</a>
* @version $Id: CmisRegistryFactoryFinder.java 1677 2010-09-09 10:47:27Z ur3cma
* $
*/
class CmisRegistryFactoryFinder
{
/** Logger. */
private static final Logger LOG = Logger.getLogger(CmisRegistryFactoryFinder.class);
/**
* Find implementation of CmisRegistryFactory Class. Lookup done in next
* order:
* <ul>
* <li>Check system property with name 'org.xcmis.CmisRegistryFactory'. If it
* set then try lookup and instantiate class with the name as property value.
* </li>
* <li>Lookup resource
* 'META-INF/services/xcmis/org.xcmis.CmisRegistryFactory'. Try read
* implementation class name from resource if it was found. Lookup and
* instantiate class with delivered name.</li>
* </ul>
*
* @return CmisRegistryFactory implementation or <code>null</code> if it
* can't be resolved
*/
public static CmisRegistryFactory findCmisRegistry()
{
String name = null;
try
{
name = System.getProperty(CmisRegistry.XCMIS_REGISTRY_FACTORY);
if (name != null)
{
return createInstance(null, name);
}
}
catch (SecurityException se)
{
if (LOG.isDebugEnabled())
LOG.error(se.getMessage(), se);
}
String file = "META-INF/services/xcmis/" + CmisRegistry.XCMIS_REGISTRY_FACTORY;
InputStream in = null;
ClassLoader classLoader = null;
try
{
classLoader = Thread.currentThread().getContextClassLoader();
in = classLoader.getResourceAsStream(file);
}
catch (Exception e)
{
}
if (in == null)
{
try
{
classLoader = CmisRegistryFactoryFinder.class.getClassLoader();
in = classLoader.getResourceAsStream(file);
}
catch (Exception e)
{
if (LOG.isDebugEnabled())
LOG.error(e.getMessage(), e);
}
}
if (in == null)
{
in = ClassLoader.getSystemResourceAsStream(file);
}
if (in != null)
{
try
{
name = null;
BufferedReader rd = new BufferedReader(new InputStreamReader(in, Charset.forName("UTF-8")));
name = rd.readLine();
rd.close();
return createInstance(classLoader, name);
}
catch (IOException e)
{
if (LOG.isDebugEnabled())
LOG.error(e.getMessage(), e);
}
}
return null;
}
private static CmisRegistryFactory createInstance(ClassLoader classLoader, String name)
{
if (LOG.isDebugEnabled())
LOG.debug("Try to create " + name);
try
{
Class cls = null;
if (classLoader != null)
{
cls = classLoader.loadClass(name);
}
else
{
cls = Class.forName(name);
}
return (CmisRegistryFactory)cls.newInstance();
}
catch (ClassNotFoundException e)
{
throw new CmisRuntimeException("Registry " + name + " not found. ", e);
}
catch (Exception e1)
{
throw new CmisRuntimeException("Can't instantiate factory " + name, e1);
}
}
}