/*
* Copyright 2007 JBoss Inc
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* Created on Jun 20, 2007
*/
package org.drools.base.accumulators;
import java.io.Serializable;
import org.drools.WorkingMemory;
import org.drools.base.mvel.DroolsMVELFactory;
import org.drools.common.InternalFactHandle;
import org.drools.rule.Declaration;
import org.drools.spi.Accumulator;
import org.drools.spi.Tuple;
import org.mvel.MVEL;
/**
* An MVEL accumulator function executor implementation
*
* @author etirelli
*/
public class MVELAccumulatorFunctionExecutor
implements
Accumulator {
private static final long serialVersionUID = 400L;
private final Serializable dummy = new Serializable() {
private static final long serialVersionUID = 8250088684994959861L;
};
private final DroolsMVELFactory model;
private final Serializable expression;
private final AccumulateFunction function;
public MVELAccumulatorFunctionExecutor(final DroolsMVELFactory factory,
final Serializable expression,
final AccumulateFunction function) {
super();
this.model = factory;
this.expression = expression;
this.function = function;
}
/* (non-Javadoc)
* @see org.drools.spi.Accumulator#createContext()
*/
public Object createContext() {
return this.function.createContext();
}
/* (non-Javadoc)
* @see org.drools.spi.Accumulator#init(java.lang.Object, org.drools.spi.Tuple, org.drools.rule.Declaration[], org.drools.WorkingMemory)
*/
public void init(Object workingMemoryContext,
Object context,
Tuple leftTuple,
Declaration[] declarations,
WorkingMemory workingMemory) throws Exception {
this.function.init( context );
}
/* (non-Javadoc)
* @see org.drools.spi.Accumulator#accumulate(java.lang.Object, org.drools.spi.Tuple, org.drools.common.InternalFactHandle, org.drools.rule.Declaration[], org.drools.rule.Declaration[], org.drools.WorkingMemory)
*/
public void accumulate(Object workingMemoryContext,
Object context,
Tuple leftTuple,
InternalFactHandle handle,
Declaration[] declarations,
Declaration[] innerDeclarations,
WorkingMemory workingMemory) throws Exception {
DroolsMVELFactory factory = (DroolsMVELFactory) workingMemoryContext;
factory.setContext( leftTuple,
null,
handle.getObject(),
workingMemory,
null );
final Object value = MVEL.executeExpression( this.expression,
this.dummy,
factory );
this.function.accumulate( context,
value );
}
public void reverse(Object workingMemoryContext,
Object context,
Tuple leftTuple,
InternalFactHandle handle,
Declaration[] declarations,
Declaration[] innerDeclarations,
WorkingMemory workingMemory) throws Exception {
DroolsMVELFactory factory = (DroolsMVELFactory) workingMemoryContext;
factory.setContext( leftTuple,
null,
handle.getObject(),
workingMemory,
null );
final Object value = MVEL.executeExpression( this.expression,
this.dummy,
factory );
this.function.reverse( context,
value );
}
/* (non-Javadoc)
* @see org.drools.spi.Accumulator#getResult(java.lang.Object, org.drools.spi.Tuple, org.drools.rule.Declaration[], org.drools.WorkingMemory)
*/
public Object getResult(Object workingMemoryContext,
Object context,
Tuple leftTuple,
Declaration[] declarations,
WorkingMemory workingMemory) throws Exception {
return this.function.getResult( context );
}
public boolean supportsReverse() {
return this.function.supportsReverse();
}
public Object createWorkingMemoryContext() {
return this.model.clone();
}
}