生成一个唯一的6位字符编码（到2063年前一直生效）的JAVA 方法

public String unRepeatSixCode() {

String sixChar = "";

SimpleDateFormat sdf = new SimpleDateFormat("yyMMddHHmmss");

Date date = new Date();

String time = sdf.format(date);

for (int i = 0; i < time.length() / 2; i++) {

String singleChar;

String x = time.substring(i * 2, (i + 1) * 2);

int b = Integer.parseInt(x);

if (b < 10) {

singleChar = Integer.toHexString(Integer.parseInt(x));

} else if (b >= 10 && b < 36) {

singleChar = String.valueOf((char) (Integer.parseInt(x) + 55));

} else {

singleChar = String.valueOf((char) (Integer.parseInt(x) + 61));

}

sixChar = sixChar + singleChar;

}

System.out.println("生成一个6位不可重复的字符编码是：" + sixChar);

return sixChar;

}