package org.drools.reteoo;
/*
* $Id: RuleBaseImpl.java,v 1.5 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.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.WeakHashMap;
import org.drools.FactException;
import org.drools.FactHandle;
import org.drools.RuleBase;
import org.drools.WorkingMemory;
import org.drools.conflict.DefaultConflictResolver;
import org.drools.rule.Rule;
import org.drools.spi.ConflictResolver;
import org.drools.spi.PropagationContext;
import org.drools.spi.RuleBaseContext;
/**
* Implementation of <code>RuleBase</code>.
*
* @author <a href="mailto:bob@werken.com">bob mcwhirter </a>
*
* @version $Id: RuleBaseImpl.java,v 1.5 2005/08/14 22:44:12 mproctor Exp $
*/
class RuleBaseImpl
implements
RuleBase
{
// ------------------------------------------------------------
// Instance members
// ------------------------------------------------------------
/** The root Rete-OO for this <code>RuleBase</code>. */
private final Rete rete;
/** Conflict resolution strategy. */
private final ConflictResolver conflictResolver;
/** The fact handle factory. */
private final FactHandleFactory factHandleFactory;
private List ruleSets;
private Map applicationData;
private RuleBaseContext ruleBaseContext;
/* @todo: replace this with a weak HashSet */
private final transient Map workingMemories;
/** Special value when adding to the underlying map. */
private static final Object PRESENT = new Object();
// ------------------------------------------------------------
// Constructors
// ------------------------------------------------------------
/**
* Construct.
*
* @param rete
* The rete network.
*/
RuleBaseImpl(Rete rete)
{
this( rete,
DefaultConflictResolver.getInstance( ),
new DefaultFactHandleFactory( ),
null,
new HashMap( ),
new RuleBaseContext( ) );
}
/**
* Construct.
*
* @param rete
* The rete network.
* @param conflictResolver
* The conflict resolver.
* @param factHandleFactory
* The fact handle factory.
* @param ruleSets
* @param applicationData
*/
RuleBaseImpl(Rete rete,
ConflictResolver conflictResolver,
FactHandleFactory factHandleFactory,
List ruleSets,
Map applicationData,
RuleBaseContext ruleBaseContext)
{
this.rete = rete;
this.factHandleFactory = factHandleFactory;
this.conflictResolver = conflictResolver;
this.ruleSets = ruleSets;
this.applicationData = applicationData;
this.ruleBaseContext = ruleBaseContext;
this.workingMemories = new WeakHashMap();
}
// ------------------------------------------------------------
// Instance methods
// ------------------------------------------------------------
/**
* @see RuleBase
*/
public WorkingMemory newWorkingMemory()
{
return newWorkingMemory( true );
}
/**
* @see RuleBase
*/
public WorkingMemory newWorkingMemory(boolean keepReference)
{
WorkingMemoryImpl workingMemory = new WorkingMemoryImpl( this );
if ( keepReference )
{
this.workingMemories.put( workingMemory,
PRESENT );
}
return workingMemory;
}
void disposeWorkingMemory(WorkingMemory workingMemory)
{
this.workingMemories.remove( workingMemory );
}
/**
* @see RuleBase
*/
public FactHandleFactory getFactHandleFactory()
{
return this.factHandleFactory;
}
/**
* @see RuleBase
*/
public ConflictResolver getConflictResolver()
{
return this.conflictResolver;
}
/**
* Retrieve the Rete-OO network for this <code>RuleBase</code>.
*
* @return The RETE-OO network.
*/
Rete getRete()
{
return this.rete;
}
/**
* Assert a fact object.
*
* @param handle
* The handle.
* @param object
* The fact.
* @param workingMemory
* The working-memory.
*
* @throws FactException
* If an error occurs while performing the assertion.
*/
void assertObject(FactHandle handle,
Object object,
PropagationContext context,
WorkingMemoryImpl workingMemory) throws FactException
{
getRete( ).assertObject( object,
(FactHandleImpl) handle,
context,
workingMemory );
}
/**
* Retract a fact object.
*
* @param handle
* The handle.
* @param workingMemory
* The working-memory.
*
* @throws FactException
* If an error occurs while performing the retraction.
*/
void retractObject(FactHandle handle,
PropagationContext context,
WorkingMemoryImpl workingMemory) throws FactException
{
getRete( ).retractObject( (FactHandleImpl) handle,
context,
workingMemory );
}
public List getRuleSets()
{
return this.ruleSets;
}
public Map getApplicationData()
{
return this.applicationData;
}
public RuleBaseContext getRuleBaseContext()
{
return this.ruleBaseContext;
}
public void addRule(Rule rule) throws FactException
{
this.rete.addRule( rule );
Iterator it = this.workingMemories.keySet().iterator();
while ( it.hasNext() )
{
this.rete.updateWorkingMemory( ( WorkingMemoryImpl ) it.next() );
}
this.rete.ruleAdded();
}
public Set getWorkingMemories()
{
return this.workingMemories.keySet();
}
}