二分法查找(Java)

二分法查找     时间复杂度为O(logn)   

public class BiSearch {      public static int search(int[] data, int find){        int low = 0;

        int mid = 0;

        int upper = 0;          if (null == data) {            return -1;        }

        upper = data.length - 1;                while (low <= upper) {            mid = (low + upper)/2;                        if (data[mid] > find) {                upper = mid - 1;            }            else if (data[mid] < find) {                low = mid + 1;            }            else {                return mid;            }         }           return -1;    }    public static void main(String[] args) {            int[] nums = { 55, 7, 28, -3, 1, 7, 29, 0, 5, 4 };            Bisearch.sort(nums, 10);      }  }