Java工程师的进阶之路

有舍才有得

目次

• 常识面01：九年夜排序算法
  
• 常识面02：两分查找算法
  
• 常识面03：两叉树的遍历
  
• 常识面04：Spring IOC
  
• 常识面05：Spring AOP
  
• 常识面06：TCP三次握脚
  
• 常识面07：TCP四次挥脚
  

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常识面01：九年夜排序算法

[code]public class Sort {    public static void main(String[] args) {        testTime();        testSort();    }    public static void testTime() {        int[] arr = new int[10000];        for (int i = 0; i </span span class="token number"10000/spanspan class="token punctuation";/span ispan class="token operator"++/spanspan class="token punctuation")/span span class="token punctuation"{/span            arrspan class="token punctuation"[/spanispan class="token punctuation"]/span span class="token operator"=/span span class="token punctuation"(/spanspan class="token keyword"int/spanspan class="token punctuation")/span span class="token punctuation"(/spanspan class="token class-name"Math/spanspan class="token punctuation"./spanspan class="token function"random/spanspan class="token punctuation"(/spanspan class="token punctuation")/span span class="token operator"*/span span class="token number"100/span span class="token operator"+/span span class="token number"1/spanspan class="token punctuation")/spanspan class="token punctuation";/span        span class="token punctuation"}/span        span class="token keyword"long/span s span class="token operator"=/span span class="token class-name"System/spanspan class="token punctuation"./spanspan class="token function"currentTimeMillis/spanspan class="token punctuation"(/spanspan class="token punctuation")/spanspan class="token punctuation";/spanspan class="token comment"//        bubbleSort(arr);/spanspan class="token comment"//        selectionSort(arr);/spanspan class="token comment"//        insertionSort(arr);/spanspan class="token comment"//        shellSort(arr);/spanspan class="token comment"//        quickSort(arr, 0, arr.length - 1);/spanspan class="token comment"//        mergeSort(arr, 0, arr.length - 1, new int[arr.length]);/spanspan class="token comment"//        radixSort(arr);/spanspan class="token comment"//        countingSort(arr);/spanspan class="token comment"//        heapSort(arr);/span        span class="token keyword"long/span e span class="token operator"=/span span class="token class-name"System/spanspan class="token punctuation"./spanspan class="token function"currentTimeMillis/spanspan class="token punctuation"(/spanspan class="token punctuation")/spanspan class="token punctuation";/span        span class="token class-name"System/spanspan class="token punctuation"./spanoutspan class="token punctuation"./spanspan class="token function"println/spanspan class="token punctuation"(/spanspan class="token punctuation"(/spane span class="token operator"-/span sspan class="token punctuation")/span span class="token operator"+/span span class="token string""ms"/spanspan class="token punctuation")/spanspan class="token punctuation";/span    span class="token punctuation"}/span    span class="token keyword"public/span span class="token keyword"static/span span class="token keyword"void/span span class="token function"testSort/spanspan class="token punctuation"(/spanspan class="token punctuation")/span span class="token punctuation"{/span        span class="token keyword"int/spanspan class="token punctuation"[/spanspan class="token punctuation"]/span arr span class="token operator"=/span span class="token keyword"new/span span class="token keyword"int/spanspan class="token punctuation"[/spanspan class="token number"50/spanspan class="token punctuation"]/spanspan class="token punctuation";/span        span class="token keyword"for/span span class="token punctuation"(/spanspan class="token keyword"int/span i span class="token operator"=/span span class="token number"0/spanspan class="token punctuation";/span i span class="token operator"/span span class="token number"50/spanspan class="token punctuation";/span ispan class="token operator"++/spanspan class="token punctuation")/span span class="token punctuation"{/span            arrspan class="token punctuation"[/spanispan class="token punctuation"]/span span class="token operator"=/span span class="token punctuation"(/spanspan class="token keyword"int/spanspan class="token punctuation")/span span class="token punctuation"(/spanspan class="token class-name"Math/spanspan class="token punctuation"./spanspan class="token function"random/spanspan class="token punctuation"(/spanspan class="token punctuation")/span span class="token operator"*/span span class="token number"100/span span class="token operator"+/span span class="token number"1/spanspan class="token punctuation")/spanspan class="token punctuation";/span        span class="token punctuation"}/spanspan class="token comment"//        bubbleSort(arr);/spanspan class="token comment"//        selectionSort(arr);/spanspan class="token comment"//        insertionSort(arr);/spanspan class="token comment"//        shellSort(arr);/spanspan class="token comment"//        quickSort(arr, 0, arr.length - 1);/spanspan class="token comment"//        mergeSort(arr, 0, arr.length - 1, new int[arr.length]);/spanspan class="token comment"//        radixSort(arr);/spanspan class="token comment"//        countingSort(arr);/spanspan class="token comment"//        heapSort(arr);/span        span class="token class-name"System/spanspan class="token punctuation"./spanoutspan class="token punctuation"./spanspan class="token function"println/spanspan class="token punctuation"(/spanspan class="token class-name"Arrays/spanspan class="token punctuation"./spanspan class="token function"toString/spanspan class="token punctuation"(/spanarrspan class="token punctuation")/spanspan class="token punctuation")/spanspan class="token punctuation";/span    span class="token punctuation"}/span    span class="token comment"//堆排序（年夜顶堆：降序算法，小顶堆：降序算法）/span    span class="token keyword"public/span span class="token keyword"static/span span class="token keyword"void/span span class="token function"heapSort/spanspan class="token punctuation"(/spanspan class="token keyword"int/span arrspan class="token punctuation"[/spanspan class="token punctuation"]/spanspan class="token punctuation")/span span class="token punctuation"{/span        span class="token comment"//创立年夜顶堆/span        span class="token keyword"for/span span class="token punctuation"(/spanspan class="token keyword"int/span i span class="token operator"=/span arrspan class="token punctuation"./spanlength span class="token operator"//span span class="token number"2/span span class="token operator"-/span span class="token number"1/spanspan class="token punctuation";/span i span class="token operator"=/span span class="token number"0/spanspan class="token punctuation";/span ispan class="token operator"--/spanspan class="token punctuation")/span span class="token punctuation"{/span            span class="token function"heapAdjust/spanspan class="token punctuation"(/spanarrspan class="token punctuation",/span ispan class="token punctuation",/span arrspan class="token punctuation"./spanlengthspan class="token punctuation")/spanspan class="token punctuation";/span        span class="token punctuation"}/span        span class="token comment"//调解年夜顶堆/span        span class="token keyword"for/span span class="token punctuation"(/spanspan class="token keyword"int/span i span class="token operator"=/span arrspan class="token punctuation"./spanlength span class="token operator"-/span span class="token number"1/spanspan class="token punctuation";/span i span class="token operator"> 0; i--) {            //交流元素            int temp = arr;            arr = arr[0];            arr[0] = temp;            //调解新堆            heapAdjust(arr, 0, i);        }    }    //堆调解    public static void heapAdjust(int arr[], int ci, int length) {        //缓存当前结面        int temp = arr[ci];        //开端轮回调解        for (int li = ci * 2 + 1; li <span class="token operator">