java用程序实现subString功能

import java.util.Scanner;public class Cut{public static void main(String[] args){    /*实现的功能是SubString（截取一段字符串）注意一个中文字符是两个字节*/String[] aa = {"j","f","p","o","明明","j","f","[","p","q","j","f","p","0"};System.out.println("请输入要截取的起点");Scanner src = new Scanner(System.in);int start = src.nextInt();System.out.println("请输入要截取的终点");int stop = src.nextInt();String result = "";System.out.println("aa数组长度为" + aa.length);if(stop < aa.length && start < aa.length){for(int i = start; i < stop ; i++ )  { result +=aa[i];  }}else{System.out.println("您输入的长度有错误，请重新输入");}System.out.println(result);}}