AlipayClient alipayClient = new DefaultAlipayClient("https://openapi.alipay.com/gateway.do","app_id","your private_key","json","GBK","alipay_public_key","RSA2");
AlipayEcoMycarParkingOrderPayRequest request = new AlipayEcoMycarParkingOrderPayRequest();
request.setBizContent("{" +
"\"car_number\":\"浙A4B94B\"," +
"\"out_trade_no\":\"34389385009983\"," +
"\"subject\":\"黄龙国际停车场代扣缴费\"," +
"\"total_fee\":15.5," +
"\"seller_logon_id\":\"test@test.com\"," +
"\"seller_id\":\"2088101106499364\"," +
"\"parking_id\":\"201600932776682933\"," +
"\"out_parking_id\":\"4421890326382443\"," +
"\"agent_id\":\"208810110649xxxx\"," +
"\"car_number_color\":\"blue\"" +
"  }");
AlipayEcoMycarParkingOrderPayResponse response = alipayClient.execute(request);
if(response.isSuccess()){
System.out.println("调用成功");
} else {
System.out.println("调用失败");
}

IAopClient client = new DefaultAopClient("https://openapi.alipay.com/gateway.do", "app_id", "merchant_private_key", "json", "1.0", "RSA2", "alipay_public_key", "GBK", false);
AlipayEcoMycarParkingOrderPayRequest  request= new AlipayEcoMycarParkingOrderPayRequest() ;
request.BizContent="{" +
"\"car_number\":\"浙A4B94B\"," +
"\"out_trade_no\":\"34389385009983\"," +
"\"subject\":\"黄龙国际停车场代扣缴费\"," +
"\"total_fee\":15.5," +
"\"seller_logon_id\":\"test@test.com\"," +
"\"seller_id\":\"2088101106499364\"," +
"\"parking_id\":\"201600932776682933\"," +
"\"out_parking_id\":\"4421890326382443\"," +
"\"agent_id\":\"208810110649xxxx\"," +
"\"car_number_color\":\"blue\"" +
"  }";
AlipayEcoMycarParkingOrderPayResponse response=client.execute(request);
Console.WriteLine(response.Body);

$aop = new AopClient ();
$aop->gatewayUrl = 'https://openapi.alipay.com/gateway.do';
$aop->appId = 'your app_id';
$aop->rsaPrivateKey = '请填写开发者私钥去头去尾去回车，一行字符串';
$aop->alipayrsaPublicKey='请填写支付宝公钥，一行字符串';
$aop->apiVersion = '1.0';
$aop->signType = 'RSA2';
$aop->postCharset='GBK';
$aop->format='json';
$request = new AlipayEcoMycarParkingOrderPayRequest ();
$request->setBizContent("{" .
"\"car_number\":\"浙A4B94B\"," .
"\"out_trade_no\":\"34389385009983\"," .
"\"subject\":\"黄龙国际停车场代扣缴费\"," .
"\"total_fee\":15.5," .
"\"seller_logon_id\":\"test@test.com\"," .
"\"seller_id\":\"2088101106499364\"," .
"\"parking_id\":\"201600932776682933\"," .
"\"out_parking_id\":\"4421890326382443\"," .
"\"agent_id\":\"208810110649xxxx\"," .
"\"car_number_color\":\"blue\"" .
"  }");
$result = $aop->execute ( $request); 

$responseNode = str_replace(".", "_", $request->getApiMethodName()) . "_response";
$resultCode = $result->$responseNode->code;
if(!empty($resultCode)&&$resultCode == 10000){
echo "成功";
} else {
echo "失败";
}

https://openapi.alipay.com/gateway.do?timestamp=2013-01-01 08:08:08&method=alipay.eco.mycar.parking.order.pay&app_id=5343&sign_type=RSA2&sign=ERITJKEIJKJHKKKKKKKHJEREEEEEEEEEEE&version=1.0&biz_content=
  {
"car_number":"浙A4B94B",
"out_trade_no":"34389385009983",
"subject":"黄龙国际停车场代扣缴费",
"total_fee":15.5,
"seller_logon_id":"test@test.com",
"seller_id":"2088101106499364",
"parking_id":"201600932776682933",
"out_parking_id":"4421890326382443",
"agent_id":"208810110649xxxx",
"car_number_color":"blue"
  }

//为确保安全通信，需自行验证响应示例中的sign值是否为蚂蚁金服所提供。

{
	"alipay_eco_mycar_parking_order_pay_response":{
		"msg":"Success",
		"gmt_payment":"2013-11-27 15:45:57",
		"code":"10000",
		"out_trade_no":"34389385009983",
		"user_id":"2088101106499364",
		"total_fee":15.5,
		"trade_no":"7085502131376415",
		"fund_bill_list":"\" [{\"amount\":0.10, \"fund_channel\":\"40\"},{\"amount\":0.10, \"fund_channel\":\"90\"}]\""
	},
	"sign":"ERITJKEIJKJHKKKKKKKHJEREEEEEEEEEEE"
}

{
	"alipay_eco_mycar_parking_order_pay_response":{
		"msg":"Service Currently Unavailable",
		"code":"20000",
		"sub_msg":"系统繁忙",
		"sub_code":"isp.unknow-error"
	},
	"sign":"ERITJKEIJKJHKKKKKKKHJEREEEEEEEEEEE"
}