对帐单调用示例

                MchDownloadbill db = new MchDownloadbill();
		db.setAppid("wxebb14d15610d9ffc");
		db.setMch_id("151826701");
		db.setNonce_str(UUID.randomUUID().toString().replace("-", ""));
		db.setBill_date("20150805");
		db.setBill_type("ALL");
		DownloadbillResult dr = payDownloadbill(db, "1a520e4a86445f0ed470981b34729");
		
		//成功
		if(dr.getReturn_code()==null){
			System.out.println(dr.getData());
		}else{//失败
			System.out.println(dr.getResult_code());
			System.out.println(dr.getReturn_msg());
		}