数组的归并排序

package DiGui;class DArray{ private long[] theArray; private int nElems; public DArray(int max){  theArray=new long[max];  nElems=0; } public void insert(long value){  theArray[nElems]=value;        nElems++; } public void display(){  for(int j=0;j<nElems;j++)   System.out.print(theArray[j]+" ");  System.out.println(" "); } public void mergeSort(){  //需要额外的空间存储数组  long[] workSpace=new long[nElems];  recMergeSort(workSpace,0,nElems-1); } private void recMergeSort(long [] workSpace,int lowerBound,int upperBound){  if(lowerBound==upperBound)   return;  else  {   int mid=(lowerBound+upperBound)/2;   recMergeSort(workSpace,lowerBound,mid);   recMergeSort(workSpace,mid+1,upperBound);   merge(workSpace,lowerBound,mid+1,upperBound);  } } private void merge(long [] workSpace,int lowPtr,int highPtr,int upperBound){  int j=0;  int mid=highPtr-1;  int lowerBound=lowPtr;  int n=upperBound-lowerBound+1;  while(lowPtr<=mid&&highPtr<=upperBound)   if(theArray[lowPtr]<theArray[highPtr])    workSpace[j++]=theArray[lowPtr++];   else    workSpace[j++]=theArray[highPtr++];     while(lowPtr<=mid)      workSpace[j++]=theArray[lowPtr++];     while(highPtr<=upperBound)        workSpace[j++]=theArray[highPtr++];     for(j=0;j<n;j++)      theArray[lowerBound+j]=workSpace[j];  }}public class MergeSortApp {

 /**  * @param args  */ public static void main(String[] args) {  // TODO Auto-generated method stub        int maxSize=100;        DArray arr;        arr=new DArray(maxSize);        arr.insert(64);        arr.insert(55);        arr.insert(77);        arr.insert(33);        arr.insert(22);        arr.insert(11);        arr.insert(99);        arr.mergeSort();        arr.display();         }

}