/*

  * 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.commons.io.comparator;

 import java.io.File;

 import java.util.Arrays;

 import java.util.Collections;

 import java.util.Comparator;

 import java.util.List;

 /**

  * Abstract file {@link Comparator} which provides sorting for file arrays and lists.

  *

  * @version $Id: AbstractFileComparator.java 1415850 2012-11-30 20:51:39Z ggregory $

  * @since 2.0

  */

 abstract class AbstractFileComparator implements Comparator<File> {

     /**

      * Sort an array of files.

      * <p>

      * This method uses {@link Arrays#sort(Object[], Comparator)}

      * and returns the original array.

      *

      * @param files The files to sort, may be null

      * @return The sorted array

      * @since 2.0

      */

     public File[] sort(final File... files) {

         if (files != null) {

             Arrays.sort(files, this);

         }

         return files;

     }

     /**

      * Sort a List of files.

      * <p>

      * This method uses {@link Collections#sort(List, Comparator)}

      * and returns the original list.

      *

      * @param files The files to sort, may be null

      * @return The sorted list

      * @since 2.0

      */

     public List<File> sort(final List<File> files) {

         if (files != null) {

             Collections.sort(files, this);

         }

         return files;

     }

     /**

      * String representation of this file comparator.

      *

      * @return String representation of this file comparator

      */

     @Override

     public String toString() {

         return getClass().getSimpleName();

     }

 }