简单的验证码生成策略

一个简略的验证码生成策略:
public static String code(String tele){
        String []zero={"000000","00000","0000","000","00","0",""};
        int hash = tele.hashCode();
        int number= 2002340;
        long result = hash ^ number;
        long time = System.currentTimeMillis();
        result = time ^ result;
        long code = result % 1000000;
        code= code<0? -code:code;
        int len =((code + "").length());
        return zero[len]+code;
    }
	
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public static String randomNumbers(int length) {
        return randomString("0123456789", length);
    }

    public static String randomString(String baseString, int length) {
        if (StrUtil.isEmpty(baseString)) {
            return "";
        } else {
            StringBuilder sb = new StringBuilder(length);
            if (length < 1) {
                length = 1;
            }

            int baseLength = baseString.length();

            for(int i = 0; i < length; ++i) {
                int number = randomInt(baseLength);
                sb.append(baseString.charAt(number));
            }

            return sb.toString();
        }
    }