docs: @Override
  	public HTCashbillJobState getJobState(String CorpNum, String JobID, String UserID)
  			throws PopbillException {
  		if ( JobID.length() != 18 )
  			throw new PopbillException(-99999999, "작업아이디가 올바르지 않습니다.");
  		return httpget("/HomeTax/Cashbill/" + JobID + "/State", CorpNum, UserID, HTCashbillJobState.class);
  	}