交换ArrayList的两个条目

//package com.nowjava;
/*
 from 时 代 J a v a 公 众 号 
*/

import java.util.ArrayList;


public class Main {

    /**

     * swaps two entries of an ArrayList

     * 

     * @param arrayList  the ArrayList whose entries you want to swap

     * @param yin  the index of the first swapped entry

     * @param yang  the index of the other swapped entry

     */

    public static <T extends Comparable<? super T>> void swap(

            ArrayList<T> arrayList, int yin, int yang) {

        T qi = arrayList.get(yin);

        arrayList.set(yin, arrayList.get(yang));

        arrayList.set(yang, qi);

    }

}