java实现排序（冒泡、选择、快速、插入）

package com.dairujie.jedis.sort;

public class Demo {
public static void main(String[] args) {
int[] numbers = { 23, 9, 8, 4, 5, 34, 66 };
maopao(numbers);
quick(numbers);
selectSort(numbers);
insertSort(numbers);
for (int i = 0; i < numbers.length; i++) {
System.out.print(numbers[i] + "  ");
}
}

/**
* 冒泡排序
*
* @param numbers
*/
public static void maopao(int[] numbers) {
int temp = 0;
int size = numbers.length;
for (int i = 0; i < size - 1; i++) {
for (int j = 0; j < size - 1 - i; j++) {
if (numbers[j] < numbers[j + 1]) // 交换两数位置
{
temp = numbers[j];
numbers[j] = numbers[j + 1];
numbers[j + 1] = temp;
}
}
}
}

/**
*
* @param numbers
*            需要比较的数组
* @param low
*            数组最小下标
* @param high
*            数组最大下标
* @return
*/
public static int getMiddle(int[] numbers, int low, int high) {
int temp = numbers[low]; // 数组的第一个作为中轴
while (low < high) {
while (low < high && numbers[high] < temp) {
high--;
}
numbers[low] = numbers[high];// 比中轴小的记录移到低端
while (low < high && numbers[low] > temp) {
low++;
}
numbers[high] = numbers[low]; // 比中轴大的记录移到高端
}
numbers[low] = temp; // 中轴记录到尾
return low; // 返回中轴的位置
}

/**
*
* @param numbers
* @param low
* @param high
*/
public static void quickSort(int[] numbers, int low, int high) {
if (low < high) {
int middle = getMiddle(numbers, low, high); // 将numbers数组进行一分为二
quickSort(numbers, low, middle - 1); // 对低字段表进行递归排序
quickSort(numbers, middle + 1, high); // 对高字段表进行递归排序
}

}

/**
* 快速排序
*
* @param numbers
*/
public static void quick(int[] numbers) {
if (numbers.length > 0) // 查看数组是否为空
{
quickSort(numbers, 0, numbers.length - 1);
}
}

/**
* 选择排序
*
* @param numbers
*/
public static void selectSort(int[] numbers) {
int size = numbers.length;
int temp = 0;
for (int i = 0; i < size; i++) {
int k = i;
for (int j = size - 1; j > i; j--) {
if (numbers[k] > numbers[j]) {
k = j;
}
}
temp = numbers[i];
numbers[i] = numbers[k];
numbers[k] = temp;
}
}
/**
* 插入排序
* @param numbers
*/
public static void insertSort(int[] numbers) {
int size = numbers.length;
int temp = 0;
int j = 0;
for (int i = 0; i < size; i++) {
temp = numbers[i];
// 假如temp比前面的值小，则将前面的值后移
for (j = i; j > 0 && temp < numbers[j - 1]; j--) {
numbers[j] = numbers[j - 1];
}
numbers[j] = temp;
}
}
}