java ASCII 字符 与 ASCII 值（数字）互转

https://blog.csdn.net/qq_37131037/article/details/86566891

https://blog.csdn.net/z507263441/article/details/47965601

1、数字 转 ASCII 字符

System.out.print((char)Integer.parseInt(str));

2、ASCII 字符 转 数字

public static int SumStrAscii(String str){
		byte[] bytestr = str.getBytes();
		int sum = 0;
		for(int i=0;i<bytestr.length;i++){
			sum += bytestr[i];
		}
		return sum;
}