Communications link failure exception (mysql - cloud sql)

[youssef dehbi alaoui]

Hi there, we are new with this service. We created a mysql instance and we followed the documentation of using cloud sql for mysql with java (https://cloud.google.com/appengine/docs/standard/java/cloud-sql/using-cloud-sql-mysql). we tested with the sample provided by appengine (https://github.com/GoogleCloudPlatform/java-docs-samples/tree/master/appengine-java8/cloudsql). when deploying we get this exception:

org.eclipse.jetty.servlet.ServletHolder$1: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure 

 The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.

the properties we used to build the link connection is : 

<INSTANCE_CONNECTION_NAME>theplayer-game:us-central1:socialboards</INSTANCE_CONNECTION_NAME>

    <user>root</user>

    <password>password</password>

    <database>sqldemo</database>

Any idea how to handle this ?

Cheers.

[George (Cloud Platform Support)]

If you think this is an issue related to Cloud SQL, you should open an issue in the public tracker. For coding issues and general programming problems, you should post your question on stackoverflow or similar forums, where competent programmers are ready to help. 

If you'd like us to have a look at your code, you may consider sending this information via private message. This feature is available from the drop-down menu offered by the reply button at the top right of the editing windows. 

[youssef dehbi alaoui]

Thanks for replying, in fact i found that the problem is about my google appengine application. So i changed the app and everything works fine.

[George (Cloud Platform Support)]

It may be worthwhile providing more detail on the solution. Other people in the same situation should find this useful.