/**
* Copyright 2010 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.
*/
package org.drools.base.mvel;
import java.io.Externalizable;
import java.io.IOException;
import java.io.ObjectInput;
import java.io.ObjectOutput;
import java.io.Serializable;
import org.drools.WorkingMemory;
import org.drools.common.InternalRuleBase;
import org.drools.rule.MVELDialectRuntimeData;
import org.drools.rule.Package;
import org.drools.spi.Consequence;
import org.drools.spi.KnowledgeHelper;
import org.mvel2.MVEL;
import org.mvel2.compiler.CompiledExpression;
import org.mvel2.debug.DebugTools;
public class MVELConsequence
implements
Consequence,
MVELCompileable,
Externalizable {
private static final long serialVersionUID = 510l;
private MVELCompilationUnit unit;
private String id;
private Serializable expr;
private DroolsMVELFactory prototype;
public MVELConsequence() {
}
public MVELConsequence(final MVELCompilationUnit unit,
final String id) {
this.unit = unit;
this.id = id;
}
public void readExternal(ObjectInput in) throws IOException,
ClassNotFoundException {
unit = (MVELCompilationUnit) in.readObject();
id = in.readUTF();
}
public void writeExternal(ObjectOutput out) throws IOException {
out.writeObject( unit );
out.writeUTF( id );
}
public void compile(ClassLoader classLoader) {
expr = unit.getCompiledExpression( classLoader );
prototype = unit.getFactory();
}
public void evaluate(final KnowledgeHelper knowledgeHelper,
final WorkingMemory workingMemory) throws Exception {
DroolsMVELFactory factory = (DroolsMVELFactory) this.prototype.clone();
factory.setContext( knowledgeHelper.getTuple(),
knowledgeHelper,
null,
workingMemory,
null );
// do we have any functions for this namespace?
Package pkg = workingMemory.getRuleBase().getPackage( "MAIN" );
if ( pkg != null ) {
MVELDialectRuntimeData data = (MVELDialectRuntimeData) pkg
.getDialectRuntimeRegistry().getDialectData( this.id );
factory.setNextFactory( data.getFunctionFactory() );
}
CompiledExpression compexpr = (CompiledExpression) this.expr;
pkg = knowledgeHelper.getWorkingMemory().getRuleBase().getPackage(knowledgeHelper.getRule().getPackage() );
ClassLoader tempClassLoader = Thread.currentThread().getContextClassLoader();
Thread.currentThread().setContextClassLoader( ((InternalRuleBase) workingMemory.getRuleBase()).getRootClassLoader() );
try {
if ( MVELDebugHandler.isDebugMode() ) {
if ( MVELDebugHandler.verbose ) {
System.out.println( "Executing expression " + compexpr.getSourceName() );
System.out.println( DebugTools.decompile( compexpr ) );
}
MVEL.executeDebugger( compexpr,
null,
factory );
} else {
MVEL.executeExpression( compexpr,
null,
factory );
}
} finally {
Thread.currentThread().setContextClassLoader( tempClassLoader );
}
}
public Serializable getCompExpr() {
return expr;
}
public String getName() {
return "default";
}
}