org.drools.compiler.rule.builder.CollectBuilder Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of drools-compiler Show documentation
The newest version!
/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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;

import org.drools.base.rule.Collect;
import org.drools.base.rule.Pattern;
import org.drools.base.rule.RuleConditionElement;
import org.drools.drl.ast.descr.BaseDescr;
import org.drools.drl.ast.descr.CollectDescr;
import org.drools.drl.ast.descr.PatternDescr;

public class CollectBuilder
    implements
    RuleConditionBuilder {

    public RuleConditionElement build(final RuleBuildContext context,
                                    final BaseDescr descr) {
        return build( context,
                      descr,
                      null );
    }

    public RuleConditionElement build(final RuleBuildContext context,
                                    final BaseDescr descr,
                                    final Pattern prefixPattern) {

        final CollectDescr collectDescr = (CollectDescr) descr;
        final PatternBuilder patternBuilder = (PatternBuilder) context.getDialect().getBuilder( PatternDescr.class );
        final Pattern sourcePattern = (Pattern) patternBuilder.build( context,
                                                                      collectDescr.getInputPattern() );

        if ( sourcePattern == null ) {
            return null;
        }

        final String className = "collect" + context.getNextId();
        collectDescr.setClassMethodName( className );
        
        Pattern resultPattern = (Pattern) context.getDeclarationResolver().peekBuildStack();

        return new Collect( sourcePattern, resultPattern );
    }

}