private void getIndex(String str){

byte[] bytes = str.getBytes();

for (int i = 0; i < bytes.length; i++) {

byte b = bytes[i];

System.out.println(b - 96);

}

}

String a = "abcdefghijklmnopqrst";

byte[] b = a.getBytes();

for (int i = 0; i < b.length; i++) {

b[i] = (byte) (b[i] - 49);

}

System.out.println(new String(b));

遍歷之后，asc碼，做減法操作。有大神給好一點(diǎn)的方案？