[Java]生成32位随机字符ID

/** * 生成32位编码 * @return string */public static String getUUID(){String uuid = UUID.randomUUID().toString().trim().replaceAll("-", "");return uuid;}/** * 自定义规则生成32位编码 * @return string */public static String getUUIDByRules(String rules)    {String radStr = rules;int rpoint = 0;        StringBuffer generateRandStr = new StringBuffer();        Random rand = new Random();        int length = 32;        for(int i=0;i<length;i++)        {        if(rules!=null){        rpoint = rules.length();        int randNum = rand.nextInt(rpoint);        generateRandStr.append(radStr.substring(randNum,randNum+1));        }        }        return generateRandStr+"";    }