/*
* Copyright 2013 Future Systems
*
* 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 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.araqne.logdb.query.aggregator;
import java.util.List;
import org.araqne.logdb.Row;
import org.araqne.logdb.query.command.NumberUtil;
import org.araqne.logdb.query.expr.Expression;
public class Range extends AbstractAggregationFunction {
private Number min;
private Number max;
public Range(List<Expression> exprs) {
super(exprs);
}
@Override
public String getName() {
return "range";
}
@Override
public void apply(Row map) {
Object obj = exprs.get(0).eval(map);
if (obj == null || !(obj instanceof Number))
return;
min = NumberUtil.min(min, obj);
max = NumberUtil.max(max, obj);
}
public Number getMin() {
return min;
}
public void setMin(Number min) {
this.min = min;
}
public Number getMax() {
return max;
}
public void setMax(Number max) {
this.max = max;
}
@Override
public Object eval() {
if (max == null && min == null)
return null;
return NumberUtil.sub(max, min);
}
@Override
public void clean() {
min = null;
max = null;
}
@Override
public AggregationFunction clone() {
Range f = new Range(exprs);
f.min = min;
f.max = max;
return f;
}
@Override
public Object[] serialize() {
Object[] l = new Object[2];
l[0] = min;
l[1] = max;
return l;
}
@Override
public void deserialize(Object[] values) {
min = (Number) values[0];
max = (Number) values[1];
}
@Override
public void merge(AggregationFunction func) {
Range other = (Range) func;
this.min = NumberUtil.min(min, other.min);
this.max = NumberUtil.max(max, other.max);
}
@Override
public String toString() {
return "range(" + exprs.get(0) + ")";
}
}