package org.drools.semantics.base;
/*
* Copyright 2004 (C) The Werken Company. All Rights Reserved.
*
* Redistribution and use of this software and associated documentation
* ("Software"), with or without modification, are permitted provided that the
* following conditions are met:
*
* 1. Redistributions of source code must retain copyright statements and
* notices. Redistributions must also contain a copy of this document.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* 3. The name "drools" must not be used to endorse or promote products derived
* from this Software without prior written permission of The Werken Company.
* For written permission, please contact bob@werken.com.
*
* 4. Products derived from this Software may not be called "drools" nor may
* "drools" appear in their names without prior written permission of The Werken
* Company. "drools" is a registered trademark of The Werken Company.
*
* 5. Due credit should be given to The Werken Company.
* (http://drools.werken.com/).
*
* THIS SOFTWARE IS PROVIDED BY THE WERKEN COMPANY AND CONTRIBUTORS ``AS IS''
* AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE WERKEN COMPANY OR ITS CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
*/
import org.drools.rule.Rule;
import org.drools.smf.Configuration;
import org.drools.smf.FactoryException;
import org.drools.smf.ObjectTypeFactory;
import org.drools.spi.ObjectType;
import org.drools.spi.RuleBaseContext;
public class SemaphoreFactory
implements
ObjectTypeFactory
{
private static final SemaphoreFactory INSTANCE = new SemaphoreFactory( );
public static SemaphoreFactory getInstance()
{
return INSTANCE;
}
public ObjectType newObjectType(Rule rule,
RuleBaseContext context,
Configuration config) throws FactoryException
{
String className = config.getAttribute( "type" );
String fieldName = "identifier";
String fieldValue = config.getAttribute( "identifier" );
if ( className == null || className.trim( ).equals( "" ) )
{
throw new FactoryException( "no Semaphore type specified" );
}
className = "org.drools.semantics.base." + className + "Semaphore";
if ( fieldValue == null || fieldValue.trim( ).equals( "" ) )
{
throw new FactoryException( "no Semaphore identifier specified" );
}
try
{
ClassLoader cl = Thread.currentThread( ).getContextClassLoader( );
if ( cl == null )
{
cl = getClass().getClassLoader();
}
Class clazz = null;
/* All semaphore types should be in system classloader*/
try
{
clazz = cl.loadClass( className );
}
catch ( ClassNotFoundException e )
{
// Semaphore type does not exist
throw new FactoryException( "Unable create Semaphore for type '" + config.getAttribute( "type" ) + "'" );
}
// make sure field getter exists
clazz.getMethod( "get" + fieldName.toUpperCase( ).charAt( 0 ) + fieldName.substring( 1 ),
( Class[] ) null );
return new ClassFieldObjectType( clazz,
fieldName,
fieldValue );
}
catch ( SecurityException e )
{
throw new FactoryException( "Field '" + fieldName + "' is not accessible for Class '" + className + "'" );
}
catch ( NoSuchMethodException e )
{
throw new FactoryException( "Field '" + fieldName + "' does not exist for Class '" + className + "'" );
}
}
}