/*
* Copyright 2006 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.rule.builder.dialect.mvel;
import java.io.Serializable;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.drools.base.mvel.DroolsMVELFactory;
import org.drools.base.mvel.MVELPredicateExpression;
import org.drools.compiler.Dialect;
import org.drools.compiler.RuleError;
import org.drools.lang.descr.PredicateDescr;
import org.drools.rule.Declaration;
import org.drools.rule.PredicateConstraint;
import org.drools.rule.builder.PredicateBuilder;
import org.drools.rule.builder.RuleBuildContext;
import org.mvel.ExpressionCompiler;
import org.mvel.MVEL;
import org.mvel.ParserContext;
/**
* @author etirelli
*
*/
public class MVELPredicateBuilder
implements
PredicateBuilder {
public void build(final RuleBuildContext context,
final List[] usedIdentifiers,
final Declaration[] previousDeclarations,
final Declaration[] localDeclarations,
final PredicateConstraint predicate,
final PredicateDescr predicateDescr) {
Map previousMap = new HashMap();
for ( int i = 0, length = previousDeclarations.length; i < length; i++ ) {
previousMap.put( previousDeclarations[i].getIdentifier(),
previousDeclarations[i] );
}
Map localMap = new HashMap();
for ( int i = 0, length = localDeclarations.length; i < length; i++ ) {
localMap.put( localDeclarations[i].getIdentifier(),
localDeclarations[i] );
}
try {
final DroolsMVELFactory factory = new DroolsMVELFactory( previousMap,
localMap,
context.getPkg().getGlobals() );
Dialect.AnalysisResult analysis = context.getDialect().analyzeExpression( context,
predicateDescr,
predicateDescr.getContent() );
final Serializable expr = ((MVELDialect) context.getDialect()).compile( (String) predicateDescr.getContent(), analysis, null, null, context );
predicate.setPredicateExpression( new MVELPredicateExpression( expr,
factory ) );
} catch ( final Exception e ) {
context.getErrors().add( new RuleError( context.getRule(),
predicateDescr,
e,
"Unable to build expression for 'inline-eval' node '" + predicateDescr.getContent() + "'\n" + e.getMessage() ) );
}
}
}