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汇总：
每轮循环确定最值；
public void bubbleSort(int[] nums){
int temp;
boolean isSort = false; //优化，发现排序好就退出
for (int i = 0; i < nums.length-1; i++) {
for (int j = 0; j < nums.length-1-i; j++) { //每次排序后能确定较大值
if(nums[j] > nums[j+1]){
isSort = true;
temp = nums[j];
nums[j] = nums[j+1];
nums[j+1] = temp;
}
}
if(!isSort){
return;
} else {
isSort = false;
}
}
}每次选出最值，再交换到边上；
public void selectSort(int[] nums){
for (int i = 0; i < nums.length-1; i++) {
int index = i;
int minNum = nums[i];
for (int j = i+1; j < nums.length; j++) {
if(nums[j] < minNum){
minNum = nums[j];
index = j;
}
}
if(index != i){
nums[index] = nums[i];
nums[i] = minNum;
}
}
}对循环的每个数找到属于自己的位置插入；
public void insertionSort(int[] nums){
for (int i = 1; i < nums.length; i++) {
int j = i;
int insertNum = nums[i];
while(j-1 >= 0 && nums[j-1] > insertNum){
nums[j] = nums[j-1];
j--;
}
nums[j] = insertNum;
}
}选一个基本值，小于它的放一边，大于它的放另一边；
public void quickSortDfs(int[] nums, int left, int right){
if(left > right){
return;
}
int l = left;
int r = right;
int baseNum = nums[left];
while(l < r){
//必须右边先走
while(nums[r] >= baseNum && l < r){
r--;
}
while(nums[l] <= baseNum && l < r){
l++;
}
int temp = nums[l];
nums[l] = nums[r];
nums[r] = temp;
}
nums[left] = nums[l];
nums[l] = baseNum;
quickSortDfs(nums, left, r-1);
quickSortDfs(nums, l+1, right);
}分治算法；
//归
public void mergeSortDfs(int[] nums, int l, int r){
if(l >= r){
return;
}
int m = (l+r)/2;
mergeSortDfs(nums, l, m);
mergeSortDfs(nums, m+1, r);
merge(nums, l, m, r);
}
//并
private void merge(int[] nums, int left, int mid, int right){
int[] temp = new int[right-left+1];
int l = left;
int m = mid+1;
int i = 0;
while(l <= mid && m <= right){
if(nums[l] < nums[m]){
temp[i++] = nums[l++];
} else {
temp[i++] = nums[m++];
}
}
while(l <= mid){
temp[i++] = nums[l++];
}
while(m <= right){
temp[i++] = nums[m++];
}
System.arraycopy(temp, 0, nums, left, temp.length);
}引入步长减少数字交换次数提高效率；
public void shellBubbleSort(int[] nums){
for (int step = nums.length/2; step > 0 ; step /= 2) {
for (int i = step; i < nums.length; i++) {
for (int j = i-step; j >= 0; j -= step) {
if(nums[j] > nums[j+step]){
int temp = nums[j];
nums[j] = nums[j+step];
nums[j+step] = temp;
}
}
}
}
}public void shellInsertSort(int[] nums){
for (int step = nums.length/2; step > 0; step /= 2) {
for (int i = step; i < nums.length; i++) {
int j = i;
int insertNum = nums[i];
while(j-step >= 0 && nums[j-step] > insertNum){
nums[j] = nums[j-step];
j-=step;
}
nums[j] = insertNum;
}
}
}大顶堆实现升序，每次将最大值移到堆的最后一个位置上；
public void heapSort2(int[] nums) {
for(int i = nums.length/2-1; i >= 0; i--){
sift(nums, i, nums.length);
}
for (int i = nums.length-1; i > 0; i--) {
int temp = nums[0];
nums[0] = nums[i];
nums[i] = temp;
sift(nums, 0, i);
}
}
private void sift(int[] nums, int parent, int len) {
int value = nums[parent];
for (int child = 2*parent +1; child < len; child = child*2 +1) {
if(child+1 < len && nums[child+1] > nums[child]){
child++;
}
if(nums[child] > value){
nums[parent] = nums[child];
parent = child;
} else {
break;
}
}
nums[parent] = value;
}按顺序统计每个数出现次数；
public void countSort(int[] nums){
int max = Integer.MIN_VALUE;
int min = Integer.MAX_VALUE;
for(int num : nums){
max = Math.max(max, num);
min = Math.min(min, num);
}
int[] countMap = new int[max-min+1];
for(int num : nums){
countMap[num-min]++;
}
int i = 0;
int j = 0;
while(i < nums.length && j < countMap.length){
if(countMap[j] > 0){
nums[i] = j+min;
i++;
countMap[j]--;
} else {
j++;
}
}
}类似计数排序，不同点在于统计的是某个区间（桶）里的数；
public void bucketSort(int[] nums){
int max = Integer.MIN_VALUE;
int min = Integer.MAX_VALUE;
for(int num : nums){
max = Math.max(max, num);
min = Math.min(min, num);
}
int bucketCount = (max-min)/nums.length+1;
List<List<Integer>> bucketList = new ArrayList<>();
for (int i = 0; i < bucketCount; i++) {
bucketList.add(new ArrayList<>());
}
for(int num : nums){
int index = (num-min)/nums.length;
bucketList.get(index).add(num);
}
for(List<Integer> bucket : bucketList){
Collections.sort(bucket);
}
int j = 0;
for(List<Integer> bucket : bucketList){
for(int num : bucket){
nums[j] = num;
j++;
}
}
}按个、十、百位依次归类排序；
public void radixSort(int[] nums){
int min = Integer.MAX_VALUE;
int max = Integer.MIN_VALUE;
for (int num : nums) {
min = Math.min(min, num);
max = Math.max(max, num);
}
for (int i = 0; i < nums.length; i++) {
nums[i] -= min;
}
max -= min;
int maxLen = (max+"").length();
int[][] bucket = new int[nums.length][10];
int[] bucketCount = new int[10];
for (int i = 0, n = 1; i < maxLen; i++, n*=10) {
for (int num : nums) {
int digitVal = num / n % 10;
bucket[bucketCount[digitVal]][digitVal] = num;
bucketCount[digitVal]++;
}
int index = 0;
for (int j = 0; j < bucketCount.length; j++) {
if(bucketCount[j] > 0){
for (int k = 0; k < bucketCount[j]; k++) {
nums[index] = bucket[k][j];
index++;
}
}
bucketCount[j] = 0;
}
}
for (int i = 0; i < nums.length; i++) {
nums[i] += min;
}
}public void priorityQueueSort(int[] nums){
PriorityQueue<Integer> queue = new PriorityQueue<>();
for(int num : nums){
queue.offer(num);
}
for (int i = 0; i < nums.length; i++) {
nums[i] = queue.poll();
}
}public void arraysApiSort(int[] nums){
Arrays.sort(nums);
}读到这里，这篇“Java常见排序算法怎么实现”文章已经介绍完毕，想要掌握这篇文章的知识点还需要大家自己动手实践使用过才能领会，如果想了解更多相关内容的文章，欢迎关注亿速云行业资讯频道。
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