algebricks/algebricks-rewriter/src/main/java/edu/uci/ics/hyracks/algebricks/rewriter/rules/ReinferAllTypesRule.java

/*
 * Copyright 2009-2013 by The Regents of the University of California
 * 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 from
 * 
 *     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 edu.uci.ics.hyracks.algebricks.rewriter.rules;

import org.apache.commons.lang3.mutable.Mutable;

import edu.uci.ics.hyracks.algebricks.common.exceptions.AlgebricksException;
import edu.uci.ics.hyracks.algebricks.core.algebra.base.ILogicalOperator;
import edu.uci.ics.hyracks.algebricks.core.algebra.base.ILogicalPlan;
import edu.uci.ics.hyracks.algebricks.core.algebra.base.IOptimizationContext;
import edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.AbstractLogicalOperator;
import edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.AbstractOperatorWithNestedPlans;
import edu.uci.ics.hyracks.algebricks.core.rewriter.base.IAlgebraicRewriteRule;

public class ReinferAllTypesRule implements IAlgebraicRewriteRule {

    @Override
    public boolean rewritePost(Mutable<ILogicalOperator> opRef, IOptimizationContext context)
            throws AlgebricksException {
        return false;
    }

    @Override
    public boolean rewritePre(Mutable<ILogicalOperator> opRef, IOptimizationContext context) throws AlgebricksException {
        if (context.checkIfInDontApplySet(this, opRef.getValue())) {
            return false;
        }
        typeOpRec(opRef, context);
        return true;
    }

    private void typePlan(ILogicalPlan p, IOptimizationContext context) throws AlgebricksException {
        for (Mutable<ILogicalOperator> r : p.getRoots()) {
            typeOpRec(r, context);
        }
    }

    private void typeOpRec(Mutable<ILogicalOperator> r, IOptimizationContext context) throws AlgebricksException {
        AbstractLogicalOperator op = (AbstractLogicalOperator) r.getValue();
        for (Mutable<ILogicalOperator> i : op.getInputs()) {
            typeOpRec(i, context);
        }
        if (op.hasNestedPlans()) {
            for (ILogicalPlan p : ((AbstractOperatorWithNestedPlans) op).getNestedPlans()) {
                typePlan(p, context);
            }
        }
        context.computeAndSetTypeEnvironmentForOperator(op);
        context.addToDontApplySet(this, op);
    }

}