// 字符串下划线转驼峰
const formatToHump = (value) => {
  return value.replace(/\_(\w)/g, (_, letter) => letter.toUpperCase())
}

// 字符串驼峰转下划线
const formatToLine = (value) => {
  return value.replace(/([A-Z])/g, '_$1').toLowerCase()
}

  private static final char UNDERLINE='_'; 
     /**
 * 下划线 转 驼峰
 * @param param
 * @return
 */
public static String underlineToCamel(String param){ 
    if (param==null||"".equals(param.trim())){  
        return "";  
    }  
    int len=param.length();  
    StringBuilder sb=new StringBuilder(len);  
    for (int i = 0; i < len; i++) {  
        char c = Character.toLowerCase(param.charAt(i));  
        if (c == UNDERLINE){  
            if (++i<len){  
                sb.append(Character.toUpperCase(param.charAt(i)));  
            }  
        }else{  
            sb.append(c);  
        }  
    }  
    return sb.toString();  
} 

     /**
 * 驼峰命名转为下划线命名
 * @param para
 * @return
 */
public static String HumpToUnderline(String para){
    StringBuilder sb=new StringBuilder(para);
    int temp=0;//定位
    if (!para.contains("_")) {
        for(int i=0;i<para.length();i++){
            if(Character.isUpperCase(para.charAt(i))){
                sb.insert(i+temp, "_");
                temp+=1;
                }
            }
        }
        return sb.toString().toUpperCase();
    }