/*
* 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.compiler.rule.builder.dialect.mvel;
import static org.drools.compiler.rule.builder.dialect.DialectUtil.copyErrorLocation;
import java.util.Arrays;
import java.util.Map;
import org.drools.compiler.compiler.AnalysisResult;
import org.drools.compiler.compiler.BoundIdentifiers;
import org.drools.compiler.compiler.DescrBuildError;
import org.drools.compiler.lang.descr.BaseDescr;
import org.drools.compiler.lang.descr.EvalDescr;
import org.drools.compiler.rule.builder.RuleBuildContext;
import org.drools.compiler.rule.builder.RuleConditionBuilder;
import org.drools.core.base.mvel.MVELCompilationUnit;
import org.drools.core.base.mvel.MVELEvalExpression;
import org.drools.core.reteoo.RuleTerminalNode.SortDeclarations;
import org.drools.core.rule.Declaration;
import org.drools.core.rule.EvalCondition;
import org.drools.core.rule.EvalCondition.SafeEvalExpression;
import org.drools.core.rule.MVELDialectRuntimeData;
import org.drools.core.rule.Pattern;
import org.drools.core.rule.RuleConditionElement;
import org.drools.core.spi.KnowledgeHelper;
import org.kie.internal.security.KiePolicyHelper;
public class MVELEvalBuilder
implements
RuleConditionBuilder {
public RuleConditionElement build(final RuleBuildContext context,
final BaseDescr descr) {
return build( context,
descr,
null );
}
/**
* Builds and returns an Eval Conditional Element
*
* @param context The current build context
* @param utils The current build utils instance
* @param patternBuilder not used by EvalBuilder
* @param descr The Eval Descriptor to build the eval conditional element from
*
* @return the Eval Conditional Element
*/
public RuleConditionElement build(final RuleBuildContext context,
final BaseDescr descr,
final Pattern prefixPattern) {
boolean typesafe = context.isTypesafe();
// it must be an EvalDescr
final EvalDescr evalDescr = (EvalDescr) descr;
try {
MVELDialect dialect = (MVELDialect) context.getDialect( context.getDialect().getId() );
Map<String, Declaration> decls = context.getDeclarationResolver().getDeclarations(context.getRule());
AnalysisResult analysis = context.getDialect().analyzeExpression( context,
evalDescr,
evalDescr.getContent(),
new BoundIdentifiers(context.getDeclarationResolver().getDeclarationClasses( decls ),
context.getPackageBuilder().getGlobals() ) );
final BoundIdentifiers usedIdentifiers = analysis.getBoundIdentifiers();
int i = usedIdentifiers.getDeclrClasses().keySet().size();
Declaration[] previousDeclarations = new Declaration[i];
i = 0;
for ( String id : usedIdentifiers.getDeclrClasses().keySet() ) {
previousDeclarations[i++] = decls.get( id );
}
Arrays.sort( previousDeclarations, SortDeclarations.instance );
MVELCompilationUnit unit = dialect.getMVELCompilationUnit( (String) evalDescr.getContent(),
analysis,
previousDeclarations,
null,
null,
context,
"drools",
KnowledgeHelper.class,
false );
final EvalCondition eval = new EvalCondition( previousDeclarations );
MVELEvalExpression expr = new MVELEvalExpression( unit,
dialect.getId() );
eval.setEvalExpression( KiePolicyHelper.isPolicyEnabled() ? new SafeEvalExpression(expr) : expr );
MVELDialectRuntimeData data = (MVELDialectRuntimeData) context.getPkg().getDialectRuntimeRegistry().getDialectData( "mvel" );
data.addCompileable( eval,
expr );
expr.compile( data );
return eval;
} catch ( final Exception e ) {
copyErrorLocation(e, evalDescr);
context.addError( new DescrBuildError( context.getParentDescr(),
evalDescr,
e,
"Unable to build expression for 'eval':" + e.getMessage() + " '" + evalDescr.getContent() + "'" ) );
return null;
} finally {
context.setTypesafe( typesafe );
}
}
}