Java 为什么双向冒泡排序的一个版本比另一个更快？

我有两个双向冒泡排序（鸡尾酒排序）的Java实现，用于对n个整数的列表进行排序

• 第一种是香草鸡尾酒
• 第二种方法是在每次传递之后增加一个左缓冲区或右缓冲区，因为在每次左缓冲区或右缓冲区之后，保证只对一个项目进行排序

奇怪的是，第二个实现要慢得多（对于100k整数，分别为15秒和18秒）

样品一：（“香草”）

int n=100000//数组长度，数组中的最大元素
//创建一个包含一百万个随机整数的数组
int[]数组=新的int[n]；
对于（int i=0；ib）//如果所选的两个元素顺序不正确
{
数组[i]=b；//交换元素
数组[i+1]=a；
changed=true；//标记已进行更改
totalSwaps++；//更新所做更改的数量
}
}
}
else//从右向左传递
{
对于（inti=（array.length-1）；i>0；i--）
{ 
a=阵列[i-1]；
b=数组[i]；
if（a>b）//如果所选的两个元素顺序不正确
{
数组[i-1]=b；//交换元素
数组[i]=a；
changed=true；//标记已进行更改
totalSwaps++；//更新所做更改的数量
}
}
}//结束此过程的排序
TotalPass++；
}同时（改变）；
long-endTime=System.currentTimeMillis（）；
System.out.println（）；
System.out.println（“完成了对“+n+”整数的排序。（“+（双精度）（结束时间开始时间）/1000+”秒以进行“+totalSwaps+”交换“+TotalPass+”传递）”）；

示例二：（带递增缓冲区）

int n=100000//数组长度，数组中的最大元素
//创建一个包含一百万个随机整数的数组
int[]数组=新的int[n]；
对于（int i=0；ib）//如果所选的两个元素顺序不正确
{
数组[i]=b；//交换元素
数组[i+1]=a；
changed=true；//标记已进行更改
totalSwaps++；//更新所做更改的数量
}
}
rightBuffer++；//增加
}
else//从右向左传递
{
对于（inti=（（array.length-1）-rightBuffer；i>leftBuffer；i--）
{ 
a=阵列[i-1]；
b=数组[i]；
if（a>b）//如果所选的两个元素顺序不正确
{
数组[i-1]=b；//交换元素
数组[i]=a；
changed=true；//标记已进行更改
totalSwaps++；//更新所做更改的数量
}
}
leftBuffer++；
}//结束此过程的排序
TotalPass++；
}while（已更改）；//末端分拣回路
long-endTime=System.currentTimeMillis（）；
System.out.println（）；
System.out.println（“完成了对“+n+”整数的排序。（“+（双精度）（结束时间开始时间）/1000+”秒以进行“+totalSwaps+”交换“+TotalPass+”传递）”）；

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有人能向这个Java noob解释一下发生了什么吗？

猜测合法吗。。。。第一个循环中的for循环取决于循环中不变的值。也就是说，编译器知道在运行之前将进行多少次循环。在东南部

int n = 100000; //length of array, largest element in array

        //create an array with one million random integers
        int[] array = new int[n];
        for (int i = 0; i < array.length; i++) //set each item...
        { 
            array[i] = (int)((Math.random() * n) + 1); //...to a random int 1 to n inclusive
        }

        long startTime = System.currentTimeMillis(); // start timer

        boolean changed = true; //to flag if any changes were made
        int a; // to hold each of two items
        int b;
        long totalPasses = 0; // total passes over the array
        long totalSwaps = 0; // total number of times two elements were swapped

        do
        {
            changed = false;

            if (totalPasses % 2 == 0) // pass from left to right
            {
                for (int i = 0; i < (array.length-1); i++)
                { 
                    a = array[i];
                    b = array[i+1];

                    if (a > b) // if the two selected elements are not in order
                    {
                        array[i] = b; // swap the elements
                        array[i+1] = a;
                        changed = true; // flag that a change has been made
                        totalSwaps++; // update the number of changes made
                    }
                }
            }
            else // pass from right to left
            {
                for (int i = (array.length-1); i > 0; i--)
                { 
                    a = array[i-1];
                    b = array[i];

                    if (a > b) // if the two selected elements are not in order
                    {
                        array[i-1] = b; // swap the elements
                        array[i] = a;
                        changed = true; // flag that a change has been made
                        totalSwaps++; // update the number of changes made
                    }
                }
            } // end sorting for this pass

        totalPasses++;
        } while (changed);

        long endTime = System.currentTimeMillis();

        System.out.println();
        System.out.println("Finished sorting " + n + " integers. (" + (double)(endTime-startTime)/1000 + " seconds to make " + totalSwaps + " swaps over " + totalPasses + " passes)");

int n = 100000; //length of array, largest element in array

        //create an array with one million random integers
        int[] array = new int[n];
        for (int i = 0; i < array.length; i++) //set each item...
        { 
            array[i] = (int)((Math.random() * n) + 1); //...to a random int 1 to n inclusive
        }

        /*
         * at the end of each left to right pass, increment the right buffer
         * at the end of each right to left pass, increment the left buffer
         */

        long startTime = System.currentTimeMillis(); // start timer

        boolean changed = true; //to flag if any changes were made
        int a; // to hold each of two items
        int b;
        int leftBuffer = 0; // distance from each side that is already sorted
        int rightBuffer = 0;
        long totalPasses = 0; // total passes over the array
        long totalSwaps = 0; // total number of times two elements were swapped

        do // main sorting loop
        {
            changed = false;

            if (totalPasses % 2 == 0) // pass from left to right
            {
                for (int i = leftBuffer; i < ((array.length-1)-rightBuffer); i++)
                { 
                    a = array[i];
                    b = array[i+1];

                    if (a > b) // if the two selected elements are not in order
                    {
                        array[i] = b; // swap the elements
                        array[i+1] = a;
                        changed = true; // flag that a change has been made
                        totalSwaps++; // update the number of changes made
                    }
                }
                rightBuffer++; // increment the cover for
            }
            else // pass from right to left
            {
                for (int i = ((array.length-1)-rightBuffer); i > leftBuffer; i--)
                { 
                    a = array[i-1];
                    b = array[i];

                    if (a > b) // if the two selected elements are not in order
                    {
                        array[i-1] = b; // swap the elements
                        array[i] = a;
                        changed = true; // flag that a change has been made
                        totalSwaps++; // update the number of changes made
                    }
                }
                leftBuffer++;
            } // end sorting for this pass

            totalPasses++;
        } while (changed); // end sorting loop

        long endTime = System.currentTimeMillis();

        System.out.println();
        System.out.println("Finished sorting " + n + " integers. (" + (double)(endTime-startTime)/1000 + " seconds to make " + totalSwaps + " swaps over " + totalPasses + " passes)");