/**
     * 将属性名转化为数据库表属性命名格式
     */
    fun upperCharToUnderLine(param: String?): String? {
        val p: Pattern = Pattern.compile("[A-Z]")
        if (param == null || param == "") {
            return ""
        }
        val builder = StringBuilder(param)
        val mc: Matcher = p.matcher(param)
        var i = 0
        while (mc.find()) {
            builder.replace(mc.start() + i, mc.end() + i, "_" + mc.group().toLowerCase())
            i++
        }
        if (‘_‘ == builder[0]) {
            builder.deleteCharAt(0)
        }
        return builder.toString()
    }

java 将属性名转化为数据库表属性命名格式