org.apache.asterix.runtime.aggregates.std.SqlMinMaxAggregateFunction Maven / Gradle / Ivy

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/*
 * 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.apache.asterix.runtime.aggregates.std;

import java.io.IOException;

import org.apache.asterix.om.types.ATypeTag;
import org.apache.hyracks.algebricks.common.exceptions.AlgebricksException;
import org.apache.hyracks.algebricks.runtime.base.ICopyEvaluatorFactory;
import org.apache.hyracks.data.std.api.IDataOutputProvider;

public class SqlMinMaxAggregateFunction extends AbstractMinMaxAggregateFunction {
    private final boolean isLocalAgg;

    public SqlMinMaxAggregateFunction(ICopyEvaluatorFactory[] args, IDataOutputProvider provider, boolean isMin,
            boolean isLocalAgg) throws AlgebricksException {
        super(args, provider, isMin);
        this.isLocalAgg = isLocalAgg;
    }

    @Override
    protected void processNull() {
    }

    @Override
    protected void processSystemNull() throws AlgebricksException {
        if (isLocalAgg) {
            throw new AlgebricksException("Type SYSTEM_NULL encountered in local aggregate.");
        }
    }

    @Override
    protected void finishSystemNull() throws IOException {
        // Empty stream. For local agg return system null. For global agg return null.
        if (isLocalAgg) {
            out.writeByte(ATypeTag.SYSTEM_NULL.serialize());
        } else {
            out.writeByte(ATypeTag.NULL.serialize());
        }
    }
}