58 lines
1.6 KiB
Java
58 lines
1.6 KiB
Java
|
/*
|
||
|
* Copyright (C) 2007 The Guava Authors
|
||
|
*
|
||
|
* 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 com.google.common.collect;
|
||
|
|
||
|
import static com.google.common.base.Preconditions.checkNotNull;
|
||
|
|
||
|
import java.io.Serializable;
|
||
|
|
||
|
import com.google.common.annotations.GwtCompatible;
|
||
|
|
||
|
/** An ordering that uses the natural order of the values. */
|
||
|
@GwtCompatible(serializable = true)
|
||
|
@SuppressWarnings("unchecked") // TODO(kevinb): the right way to explain this??
|
||
|
final class NaturalOrdering extends Ordering<Comparable> implements Serializable {
|
||
|
static final NaturalOrdering INSTANCE = new NaturalOrdering();
|
||
|
|
||
|
@Override
|
||
|
public int compare(Comparable left, Comparable right) {
|
||
|
checkNotNull(left); // for GWT
|
||
|
checkNotNull(right);
|
||
|
return left.compareTo(right);
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
public <S extends Comparable> Ordering<S> reverse() {
|
||
|
return (Ordering<S>) ReverseNaturalOrdering.INSTANCE;
|
||
|
}
|
||
|
|
||
|
// preserving singleton-ness gives equals()/hashCode() for free
|
||
|
private Object readResolve() {
|
||
|
return INSTANCE;
|
||
|
}
|
||
|
|
||
|
@Override
|
||
|
public String toString() {
|
||
|
return "Ordering.natural()";
|
||
|
}
|
||
|
|
||
|
private NaturalOrdering() {
|
||
|
}
|
||
|
|
||
|
private static final long serialVersionUID = 0;
|
||
|
}
|