我不知道为什么我在test.charAt(1)处得到了index out of bound。

Question

    import java.util.*;
    public class Kata {
    public static void main(String[]args)
    {
     Scanner scan = new Scanner(System.in);
     System.out.println("Enter a text to encrypt:");
     //to read the whole line
     String text = scan.nextLine();
     System.out.println(encryptThis(text));
    }
    public static String encryptThis(String text) {
     //words are separated by just one white space between them. 
     //In order to split it and get the array of words, just call the split()

     String [] array = text.split("");
     String encrypt = "";

     for(int j = 0; j < array.length;j++)
     {
            String test = array[j];
            //get first character
            char first = test.charAt(0);
           //convert the first character into ASCII code;
            int ascii = (int) first;

           encrypt+=ascii;
          char second = test.charAt(1);
          char last = test.charAt(test.length()-1);

              encrypt+=last;
              for(int i = 2; i < text.length()-1;i++)
              {
                  encrypt+=test.charAt(i);
              }
              encrypt+=second + " ";               
      }
    return encrypt;
    } 
    }

线程 "main "中的异常 java.lang.StringIndexOutOfBoundsException。String index out of range: 1我不知道为什么我的索引超出了范围，请帮助我，我正试图写一个程序来加密信息。

Answer 1

String test = array[j]; 只取数组中的第j个字符，并对其进行加密。test.charAt(1) 会使代码失败。围绕这一点写几条打印语句来进一步调试

Answer 2

在访问该位置的字符前添加一个检查

char second = null;
if(test.length > 1) {
  second = test.charAt(1);
}