Here you can find the source of swap(T[] data, int a, int b)
public static <T extends Comparable<? super T>> void swap(T[] data, int a, int b)
//package com.java2s; //<div>Icons made by <a href="http://www.flaticon.com/authors/freepik" title="Freepik">Freepik</a> from <a href="http://www.flaticon.com" title="Flaticon">www.flaticon.com</a> is licensed by <a href="http://creativecommons.org/licenses/by/3.0/" title="Creative Commons BY 3.0" target="_blank">CC 3.0 BY</a></div> public class Main { public static <T extends Comparable<? super T>> void swap(T[] data, int a, int b) { T temp = data[a];//from w w w .ja va 2s . c o m data[a] = data[b]; data[b] = temp; } }