Java实现的快速排序算法，Java实现排序算法, import java

Java实现的快速排序算法，Java实现排序算法, import java

 import java.util.Arrays; import java.util.Random; public class QuickSort {     public static final Random RND = new Random();     private static void swap(Object[] array, int i, int j) {         Object tmp = array[i];         array[i] = array[j];         array[j] = tmp;     }     private static <E extends Comparable<? super E>> int partition(E[] array, int begin, int end) {         int index = begin + RND.nextInt(end - begin + 1);         E pivot = array[index];         swap(array, index, end);         for (int i = index = begin; i < end; ++i) {             if (array[i].compareTo(pivot) <= 0) {                 swap(array, index++, i);             }         }         swap(array, index, end);         return (index);     }     private static <E extends Comparable<? super E>> void qsort(E[] array, int begin, int end) {         if (end > begin) {             int index = partition(array, begin, end);             qsort(array, begin, index - 1);             qsort(array, index + 1, end);         }     }     public static <E extends Comparable<? super E>> void sort(E[] array) {         qsort(array, 0, array.length - 1);     }     // Example uses     public static void main(String[] args) {         Integer[] l1 = { 5, 1024, 1, 88, 0, 1024 };         System.out.println("l1  start:" + Arrays.toString(l1));         QuickSort.sort(l1);         System.out.println("l1 sorted:" + Arrays.toString(l1));         String[] l2 = { "gamma", "beta", "alpha", "zoolander" };         System.out.println("l2  start:" + Arrays.toString(l2));         QuickSort.sort(l2);         System.out.println("l2 sorted:" + Arrays.toString(l2));     } }Analogously to the Erlang solution above, a user-supplied {{Javadoc:SE|java/util|Comparator}} determines the partial ordering of array elements: import java.util.Comparator; import java.util.Random; public class Quicksort {     public static final Random RND = new Random();      private static void swap(Object[] array, int i, int j) {         Object tmp = array[i];         array[i] = array[j];         array[j] = tmp;     }     private static <E> int partition(E[] array, int begin, int end, Comparator<? super E> cmp) {         int index = begin + RND.nextInt(end - begin + 1);         Object pivot = array[index];         swap(array, index, end);            for (int i = index = begin; i < end; ++ i) {             if (cmp.compare(array[i], pivot) <= 0) {                 swap(array, index++, i);             }         }         swap(array, index, end);            return (index);     }     private static <E> void qsort(E[] array, int begin, int end, Comparator<? super E> cmp) {         if (end > begin) {             int index = partition(array, begin, end, cmp);             qsort(array, begin, index - 1, cmp);             qsort(array, index + 1,  end,  cmp);         }     }     public static <E> void sort(E[] array, Comparator<? super E> cmp) {         qsort(array, 0, array.length - 1, cmp);     } }