i was try use this link to get direction \"http://maps.googleapis.com/maps/api/directions/xml?origin=10.933952,106.863352&destination=10.9490721,106.8574901&sensor=f
https://developers.google.com/maps/documentation/business/articles/usage_limits#limitexceeded
You can exceed the Google Maps API Web Services usage limits by:
Sending too many requests per day. Sending requests too fast, i.e. too many requests per second. Sending requests too fast for too long or otherwise abusing the web service. Exceeding other usage limits, e.g. points per request in the Elevation API.
Upon receiving a response with status code OVER_QUERY_LIMIT, your application should determine which usage limit has been exceeded. This can be done by pausing for 2 seconds and resending the same request. If status code is still OVER_QUERY_LIMIT, your application is sending too many requests per day. Otherwise, your application is sending too many requests per second.