package org.drools.examples.house;
/*
* $Id: HouseConditionFactory.java,v 1.2 2005/05/08 04:22:34 dbarnett Exp $
*
* Copyright 2005-2005 (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 java.util.ArrayList;
import java.util.List;
import org.drools.rule.Declaration;
import org.drools.rule.InvalidRuleException;
import org.drools.rule.Rule;
import org.drools.semantics.base.ClassObjectType;
import org.drools.smf.ConditionFactory;
import org.drools.smf.Configuration;
import org.drools.smf.FactoryException;
import org.drools.spi.Condition;
import org.drools.spi.ConditionException;
import org.drools.spi.RuleBaseContext;
import org.drools.spi.Tuple;
public class HouseConditionFactory
implements
ConditionFactory
{
public Condition[] newCondition(Rule rule,
RuleBaseContext context,
Configuration config) throws FactoryException
{
Configuration childConfig = null;
Configuration[] configurations = config.getChildren( );
List conditions = new ArrayList( );
for ( int i = 0; i < configurations.length; i++ )
{
childConfig = configurations[i];
if ( childConfig.getName( ).equals( "room" ) )
{
conditions.add( processRoom( rule,
childConfig ) );
}
}
return (Condition[]) conditions.toArray( new Condition[conditions.size( )] );
}
private Condition processRoom(Rule rule,
Configuration config) throws FactoryException
{
Configuration childConfig = null;
final String roomName = config.getAttribute( "name" );
final Declaration roomDeclaration = getDeclaration( rule,
Room.class,
roomName );
Condition condition = null;
Configuration[] configurations = config.getChildren( );
for ( int i = 0; i < configurations.length; i++ )
{
childConfig = configurations[i];
if ( childConfig.getName( ).equals( "temperature" ) )
{
final Declaration[] declarations = new Declaration[]{roomDeclaration};
childConfig = childConfig.getChildren( )[0];
final int kelvin = getKelvin( childConfig.getAttribute( "scale" ),
childConfig.getText( ) );
if ( childConfig.getName( ).equals( "less-than" ) )
{
condition = new Condition( )
{
public Declaration[] getRequiredTupleMembers()
{
return declarations;
}
public boolean isAllowed(Tuple tuple) throws ConditionException
{
Room room = (Room) tuple.get( roomDeclaration );
if (!roomName.equals(room.getName()))
{
return false;
}
if ( room.getTemperature( ) < kelvin )
{
return true;
}
else
{
return false;
}
}
};
}
else if ( childConfig.getName( ).equals( "greater-than" ) )
{
condition = new Condition( )
{
public Declaration[] getRequiredTupleMembers()
{
return declarations;
}
public boolean isAllowed(Tuple tuple) throws ConditionException
{
Room room = (Room) tuple.get( roomDeclaration );
if (!roomName.equals(room.getName()))
{
return false;
}
if ( room.getTemperature( ) > kelvin )
{
return true;
}
else
{
return false;
}
}
};
}
}
}
return condition;
}
private Declaration getDeclaration(Rule rule,
Class clazz,
String identifier) throws FactoryException
{
Declaration declaration = rule.getParameterDeclaration( identifier );
if ( declaration == null )
{
ClassObjectType type = new ClassObjectType( clazz );
try
{
declaration = rule.addParameterDeclaration( identifier,
type );
}
catch ( InvalidRuleException e )
{
throw new FactoryException( "xxx" );
}
}
return declaration;
}
private int getKelvin(String scale,
String value)
{
int i = Integer.parseInt( value );
if ( scale.equals( "F" ) )
{
i = (int) Math.round( (i - 32) / 1.8 + 273 );
}
if ( scale.equals( "C" ) )
{
i = i + 273;
}
return i;
}
}