/*
* 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.phoenix.expression.function;
import java.util.List;
import org.apache.hadoop.conf.Configuration;
import org.apache.phoenix.expression.Expression;
import org.apache.phoenix.expression.aggregator.Aggregator;
import org.apache.phoenix.expression.aggregator.MaxAggregator;
import org.apache.phoenix.parse.FunctionParseNode.Argument;
import org.apache.phoenix.parse.FunctionParseNode.BuiltInFunction;
import org.apache.phoenix.parse.MaxAggregateParseNode;
import org.apache.phoenix.schema.SortOrder;
import org.apache.phoenix.schema.PDataType;
/**
* Built-in function for finding MAX.
*
*
* @since 0.1
*/
@BuiltInFunction(name=MaxAggregateFunction.NAME, nodeClass=MaxAggregateParseNode.class, args= {@Argument()} )
public class MaxAggregateFunction extends MinAggregateFunction {
public static final String NAME = "MAX";
public MaxAggregateFunction() {
}
public MaxAggregateFunction(List<Expression> childExpressions, CountAggregateFunction delegate) {
super(childExpressions, delegate);
}
@Override
public Aggregator newServerAggregator(Configuration conf) {
final PDataType type = getAggregatorExpression().getDataType();
SortOrder sortOrder = getAggregatorExpression().getSortOrder();
return new MaxAggregator(sortOrder) {
@Override
public PDataType getDataType() {
return type;
}
};
}
@Override
public String getName() {
return NAME;
}
@Override
public SortOrder getSortOrder() {
return getAggregatorExpression().getSortOrder();
}
}