使用二分法查找数组中元素的位置

public class BinarySearch{
    
    int[] a = {6,9,4,14,3,2,1,8,9,12,10,5,7};
    
    void bubbleSort(int[] a){
        
        if(a.length == 0){
            System.out.println("错误!数组长度不能为0");
            System.exit(1);
        }
        
        int temp = 0;
        
        for(int i=a.length-1;i>0;i--){
            for(int j=0;j<i;j++){
                if(a[j]>a[j+1]){
                    temp = a[j];
                    a[j] = a[j+1];
                    a[j+1] = temp;
                }
            }
        }
    }
    
    void binarySearch(int a[],int i){
        
        if(a.length == 0){
            System.out.println("错误!数组长度不能为0");
            System.exit(1);
        }
        
        bubbleSort(a);
　　　   int m = 0;
        int start = 0;
        int end = a.length - 1;
        
        while(start <= end){
            m = (start + end)/2;
            if(i == a[m]){
                System.out.println(i + "排在第" + (m+1) + "个");
                System.exit(1);
            }else if (i < a[m]){
                end = m - 1;
            }else if (i > a[m]){
                start = m + 1;
            }
        }
        System.out.println("没找到这个数！");
    }
    
    public static void main(String[] args){
        BinarySearch b = new BinarySearch();
        b.binarySearch(b.a,10);
    }
    
}