Find Min In Rotated Sorted Array

public class Solution {
    /**
     * @param nums: a rotated sorted array
     * @return: the minimum number in the array
     */
    public int findMin(int[] nums) {
        // write your code here
        
        if(nums == null || nums.length == 0){
            return -1;
        }
        
        int start = 0, end = nums.length -1, target = nums[end];
        
        while(start + 1 < end){
            int mid = start + (end - start )/2;
            
            if(nums[mid] < target){
                end = mid;
            }else{
                start = mid;
            }
        }
        
        if(nums[start] <= target){
            return nums[start];
        }else{
            return nums[end];
        }
        
        
    }
}