/*
 * Copyright (C) 2014 Pedro Vicente Gómez Sánchez.
 *
 * 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.github.pedrovgs.sortingalgorithm;

/**
 * Interface to be implemented by sorting algorithm implementations in this repository.
 *
 * @author Pedro Vicente Gómez Sánchez.
 */
public interface SortingAlgorithm {

  void sort(int[] numbers);
}

@@ -802,17 +802,22 @@
 lic 
-interface
+abstract class
  Sor
@@ -835,16 +835,32 @@
 hm %7B%0A%0A  
+public abstract 
 void sor
@@ -876,11 +876,324 @@
 umbers);
+%0A%0A  protected void swap(int%5B%5D numbers, int i, int j) %7B%0A    int temp = numbers%5Bi%5D;%0A    numbers%5Bi%5D = numbers%5Bj%5D;%0A    numbers%5Bj%5D = temp;%0A  %7D%0A%0A  protected void validateInput(int%5B%5D numbers) %7B%0A    if (numbers == null) %7B%0A      throw new IllegalArgumentException(%22You can't pass a null instance as parameter.%22);%0A    %7D%0A  %7D
 %0A%7D%0A

Change SortingAlgorithm to be an abstract class instead of an interface