import java.util.Arrays; public class HeapSort {     public static void heapSort(DataWraper[] data){         System.out.println("开始排序");         int arrayLength=data.length;         //循环建堆         for(int i=0;i<arrayLength-1;i++){             //建堆             buildMaxHeap(data,arrayLength-1-i);             //交换堆顶和最后一个元素             swap(data,0,arrayLength-1-i);             System.out.println(Arrays.toString(data));         }     }     private static void swap(DataWraper[] data, int i, int j) {         // TODO Auto-generated method stub         DataWraper tmp=data[i];         data[i]=data[j];         data[j]=tmp;     }     //对data数组从0到lastIndex建大顶堆     private static void buildMaxHeap(DataWraper[] data, int lastIndex) {         // TODO Auto-generated method stub         //从lastIndex处节点（最后一个节点）的父节点开始         for(int i=(lastIndex-1)/2;i>=0;i--){             //k保存正在判断的节点             int k=i;             //如果当前k节点的子节点存在             while(k*2+1<=lastIndex){                 //k节点的左子节点的索引                 int biggerIndex=2*k+1;                 //如果biggerIndex小于lastIndex，即biggerIndex+1代表的k节点的右子节点存在                 if(biggerIndex<lastIndex){                     //若果右子节点的值较大                     if(data[biggerIndex].compareTo(data[biggerIndex+1])<0){                         //biggerIndex总是记录较大子节点的索引                         biggerIndex++;                     }                 }                 //如果k节点的值小于其较大的子节点的值                 if(data[k].compareTo(data[biggerIndex])<0){                     //交换他们                     swap(data,k,biggerIndex);                     //将biggerIndex赋予k，开始while循环的下一次循环，重新保证k节点的值大于其左右子节点的值                     k=biggerIndex;                 }else{                     break;                 }             }         }     }     public static void main(String[] args) {         // TODO Auto-generated method stub         DataWraper [] data={                 new DataWraper(21, ""),                 new DataWraper(30, ""),                 new DataWraper(49, ""),                 new DataWraper(30, "*"),                 new DataWraper(16, ""),                 new DataWraper(9, ""),         };         System.out.println("排序之前：\n"+Arrays.toString(data));         heapSort(data);         System.out.println("排序之后：\n"+Arrays.toString(data));     } }