fullstack/algebricks/algebricks-core/src/main/java/edu/uci/ics/hyracks/algebricks/core/algebra/operators/logical/AbstractBinaryJoinOperator.java

/*
 * Copyright 2009-2010 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.core.algebra.operators.logical;

import java.util.ArrayList;

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.ILogicalExpression;
import edu.uci.ics.hyracks.algebricks.core.algebra.base.ILogicalOperator;
import edu.uci.ics.hyracks.algebricks.core.algebra.base.LogicalVariable;
import edu.uci.ics.hyracks.algebricks.core.algebra.properties.VariablePropagationPolicy;
import edu.uci.ics.hyracks.algebricks.core.algebra.visitors.ILogicalExpressionReferenceTransform;

public abstract class AbstractBinaryJoinOperator extends AbstractLogicalOperator {
    protected final Mutable<ILogicalExpression> condition;
    protected JoinKind joinKind;

    public enum JoinKind {
        INNER,
        LEFT_OUTER
    }

    public AbstractBinaryJoinOperator(JoinKind joinKind, Mutable<ILogicalExpression> condition) {
        this.joinKind = joinKind;
        this.condition = condition;
    }

    public AbstractBinaryJoinOperator(JoinKind joinKind, Mutable<ILogicalExpression> condition,
            Mutable<ILogicalOperator> input1, Mutable<ILogicalOperator> input2) {
        this(joinKind, condition);
        inputs.add(input1);
        inputs.add(input2);
    }

    public Mutable<ILogicalExpression> getCondition() {
        return condition;
    }

    public JoinKind getJoinKind() {
        return joinKind;
    }

    @Override
    public void recomputeSchema() {
        schema = new ArrayList<LogicalVariable>();
        schema.addAll(inputs.get(0).getValue().getSchema());
        schema.addAll(inputs.get(1).getValue().getSchema());
    }

    @Override
    public VariablePropagationPolicy getVariablePropagationPolicy() {
        return VariablePropagationPolicy.concat(VariablePropagationPolicy.ALL, VariablePropagationPolicy.ALL);
    }

    @Override
    public boolean acceptExpressionTransform(ILogicalExpressionReferenceTransform visitor) throws AlgebricksException {
        return visitor.transform(condition);
    }

    @Override
    public boolean isMap() {
        return false;
    }
}