/**
* Copyright (C) 2015 Valkyrie RCP
*
* 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.valkyriercp.rules.closure.support;
import org.springframework.util.comparator.ComparableComparator;
import org.springframework.util.comparator.NullSafeComparator;
import org.valkyriercp.rules.closure.BinaryClosure;
/**
* Returns the maximum of two <code>Comparable</code> objects; with nulls regarded a
* being less than non null.
*
* @author Keith Donald
*/
public class Maximum extends AbstractBinaryClosure {
private static final Maximum INSTANCE = new Maximum();
private static final NullSafeComparator COMPARATOR = new NullSafeComparator(new ComparableComparator(), true);
/**
* Returns the shared instance--this is possible as the default functor for
* this class is immutable and stateless.
*
* @return the shared instance
*/
public static final BinaryClosure instance() {
return INSTANCE;
}
/**
* Return the maximum of the two Comparable objects.
*
* @param comparable1
* the first comparable
* @param comparable2
* the second comparable
* @return the maximum
*/
public Object call(Object comparable1, Object comparable2) {
int result = COMPARATOR.compare(comparable1,
comparable2);
if (result > 0) {
return comparable1;
}
else if (result < 0) {
return comparable2;
}
return comparable1;
}
public String toString() {
return "max(arg1, arg2)";
}
}