实现二分法主要有一下两种：
while循环和递归。
package interview201505;public class BinarySearch { /** * 二分查找算法 * while循环 */ public static int binarySearch(int[] data, int find){ int low = 0; int high = data.length-1; while(low < high){ int mid = (low +high)/2; if(find < data[mid]){ high = mid; }else if(find > data[mid]){ low = mid; }else if(find == data[mid]){ return mid; } } return -1; } /** * 二分法使用递归 * */ public static int binarySearch2(int[] data, int find,int low,int high){ int mid = (low+high)/2; if(data[mid] < find){ return binarySearch2(data,find,mid+1,high); }else if(data[mid] > find){ return binarySearch2(data,find,low,mid-1); }else if (data[mid] == find){ return mid; } return -1; } public static void main(String[] args){ int[] data = {1,2,3,4,5,6,7}; System.out.println(binarySearch(data, 6)); System.out.println(binarySearch2(data, 6, 0, 6)); }}