Using Google Cloud SQL with App Engine in JAVA

Excellent demo, interesting tone

Now, I am going through this tutorial

https://developers.google.com/appengine/docs/java/cloud-sql/#Java_Connect_to_your_database

Database table created. There is a SQL prompt in the Google Cloud SQL

Through almost 2 days of work, I finished. There are a few things worth mentioning

1. A JDK is required to compile JSPs to be uploaded to GAE. Should pay attention to the JDK version as GAE, currently, supports up to JAVA7. If the JSP is compiled in JAVA8, it will not work in the GAE. If you have a 64-bits Eclipse running, you require a JDK in 64-bits
   
   If you have the JDK installed properly, but you still have the UnsupportedClassVersionError from the GAE,  there are few things you have to do to make sure your app is correctly compiled.
   
   UnsupportedClassVersionError
   
   Unsupported major.minor version 52.0, java.lang.UnsupportedClassVersionError: org/apache/jsp/test1_jsp : Unsupported major.minor version 52.0
   
   If you do not require any other JRE to be run on your machine, uninstall all other JREs and JDKs. This would save you bundle of time for dragging yourself into a build path chaos
   
   If you require multiple JREs and JDKs to be run on a same machine, check your environment variables in the Control panel > Systems > Environment Variables. Make sure the path is pointing to the bin of the JDK for compilation.

1. A Cloud SQL instance can be setup in region either US, EU or Asia. If you intended to authorise your GAE app to connect to the Google Cloud SQL, they must be in the same region. Otherwise, you get a "Authorized GAE applications must be in the same region as the database instance" error.  The region setting cannot be changed once the database instance is created, and as far a I know, Google allows GAE app to be created and run in US only.