package org.drools.reteoo;
/*
* $Id: ObjectTypeNode.java,v 1.3 2005/08/14 22:44:12 mproctor Exp $
*
* Copyright 2001-2003 (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 trademark of The Werken Company.
*
* 5. Due credit should be given to The Werken Company. (http://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 java.io.Serializable;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import org.drools.FactException;
import org.drools.FactHandle;
import org.drools.NoSuchFactObjectException;
import org.drools.RetractionException;
import org.drools.spi.ObjectType;
import org.drools.spi.PropagationContext;
import org.drools.util.PrimitiveLongMap;
/**
* Filters <code>Objects</code> coming from the <code>Rete</code> using a
* <code>ObjectType</code> semantic module.
*
* <p>
* It receives <code>Objects</code> from the <code>Rete</code>, uses a
* <code>ObjectType</code> instance to determine membership, and propagates
* matching <code>Objects</code> further to all matching
* <code>ParameterNode</code>s.
* </p>
*
* @see ObjectType
* @see ParameterNode
* @see Rete
*
* @author <a href="mailto:bob@eng.werken.com">bob@eng.werken.com </a>
*/
class ObjectTypeNode extends ObjectSource
implements
ObjectSink,
Serializable,
NodeMemory
{
// ------------------------------------------------------------
// Instance members
// ------------------------------------------------------------
/** The <code>ObjectType</code> semantic module. */
private final ObjectType objectType;
private final ObjectSource objectSource;
// ------------------------------------------------------------
// Constructors
// ------------------------------------------------------------
/**
* Construct given a semantic <code>ObjectType</code>.
*
* @param objectType
* The semantic object-type differentiator.
*/
public ObjectTypeNode(int id,
ObjectType objectType,
ObjectSource objectSource)
{
super( id );
this.objectSource = objectSource;
this.objectType = objectType;
}
// ------------------------------------------------------------
// Instance methods
// ------------------------------------------------------------
/**
* Retrieve the semantic <code>ObjectType</code> differentiator.
*
* @return The semantic <code>ObjectType</code> differentiator.
*/
public ObjectType getObjectType()
{
return this.objectType;
}
public int getId()
{
return this.id;
}
/**
* Assert a new fact object into this <code>RuleBase</code> and the
* specified <code>WorkingMemory</code>.
*
* @param handle
* The fact handle.
* @param object
* The object to assert.
* @param workingMemory
* The working memory session.
* @throws FactException
* if an error occurs during assertion.
*/
public void assertObject(Object object,
FactHandleImpl handle,
PropagationContext context,
WorkingMemoryImpl workingMemory) throws FactException
{
if ( this.objectType.matches( object ) )
{
PrimitiveLongMap memory = (PrimitiveLongMap) workingMemory.getNodeMemory( this );
memory.put( handle.getId(),
handle );
propagateAssertObject( object,
handle,
context,
workingMemory );
}
}
/**
* Retract a fact object from this <code>RuleBase</code> and the specified
* <code>WorkingMemory</code>.
*
* @param handle
* The handle of the fact to retract.
* @param workingMemory
* The working memory session.
* @throws FactException
* if an error occurs during assertion.
*/
public void retractObject(FactHandleImpl handle,
PropagationContext context,
WorkingMemoryImpl workingMemory) throws FactException
{
try
{
if ( this.objectType.matches( workingMemory.getObject( handle ) ) )
{
PrimitiveLongMap memory = (PrimitiveLongMap) workingMemory.getNodeMemory( this );
memory.remove( handle.getId() );
propagateRetractObject( handle,
context,
workingMemory );
}
}
catch ( NoSuchFactObjectException e )
{
throw new RetractionException( e );
}
}
public void updateNewRule( WorkingMemoryImpl workingMemory,
PropagationContext context ) throws FactException
{
/* if this ObjectTypeNode has not been marked that a rule is being attached
* then there is no updating to do, so return.
*/
if ( !isAttachingNewRule() )
{
return;
}
PrimitiveLongMap memory = (PrimitiveLongMap) workingMemory.getNodeMemory( this );
Iterator it = memory.values().iterator();
FactHandleImpl handle = null;
Object object = null;
while ( it.hasNext() )
{
handle = (FactHandleImpl) it.next();
try
{
object = workingMemory.getObject( handle );
assertObject( object,
handle,
context,
workingMemory );
}
catch ( NoSuchFactObjectException e )
{
// do nothing, shouldn't happen
}
}
}
public void attach()
{
this.objectSource.addObjectSink( this );
}
public Object createMemory()
{
return new PrimitiveLongMap( 32,
8 );
}
}