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This is the ehcache core module. Pair it with other modules for added functionality.
/**
* Copyright 2003-2010 Terracotta, Inc.
*
* 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 net.sf.ehcache.search.aggregator;
import net.sf.ehcache.search.Attribute;
/**
* Determine the maximum value
*
* @author teck
* @param
*/
public class Max implements AggregatorInstance {
private Comparable max;
private final Attribute attribute;
/**
* @param attribute
*/
public Max(Attribute attribute) {
this.attribute = attribute;
}
/**
* {@inheritDoc}
*
* NOTE: May return null if no input provided
*/
public T aggregateResult() {
return (T) max;
}
/**
* {@inheritDoc}
*
* NOTE: null input values are ignored
*/
public void accept(Object input) throws AggregatorException {
if (input == null) {
return;
}
Comparable next = getComparable(input);
if (max == null) {
max = next;
} else if (next.compareTo(max) > 0) {
max = next;
}
}
private static Comparable getComparable(Object o) {
if (o instanceof Comparable) {
return (Comparable) o;
}
throw new AggregatorException("Value is not Comparable: " + o.getClass());
}
/**
* {@inheritDoc}
*/
public Attribute getAttribute() {
return attribute;
}
}