package cn.estsh.i3plus.pojo.base.util;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * 字符串转大写换成下滑线加小写
 */
public class StringCastUtils {
    public static String upperCharToUnderLine(String param) {
        Pattern p= Pattern.compile("[A-Z]");
        if(param==null ||param.equals("")){
          return "";
        }
         StringBuilder builder=new StringBuilder(param);
         Matcher mc=p.matcher(param);
         int i=0;
         while (mc.find()) {
             builder.replace(mc.start()+i, mc.end()+i, "_"+mc.group().toLowerCase());
             i++;
       }
       if('_' == builder.charAt(0)){
       builder.deleteCharAt(0);
     }
     return builder.toString();
    }
}
