Glassfish资源/ jndi / jdbc登录凭据配置

Question

I'm deploying my first Java web service app and just finished solving "Glassfish: Exception while preparing the app : Invalid resource : __pm". I created the glassfish-resources.xml file and placed it in my web-inf folder per http://www.oracle.com/technetwork/articles/java/pongegf-1517943.html . (It took me awhile to realize that Netbeans put the file in the wrong place to start with).

Now I'm wondering about distribution in the real world where the login credentials are buried in the WAR file via the glassfish-resources.xml file. Presumably if I ever need to change the credentials, I would have to rebuild for every server configuration I deploy to since my login credentials will be different between environments. Since we typically go through 2-3 stages of testing environments before going to production, this seems prone to introducing new errors or changes. Is there a way to maintain the login credentials in a config file that isn't part of the compiled WAR file or am I missing something more fundamental?

Thank you.

Answer 1

Normally you would setup a JDBC connection pool and use a JDBC resource to reference it. In the application you configure the JDBC resource used via the persistence.xml.

Something like this, when using the default Glassfish derby database (JDBC resource and connection are already setup for this, only the DB must be started):

 <persistence xmlns="http://java.sun.com/xml/ns/persistence" version="1.0">
 <persistence-unit name="my_persistence">
     <jta-data-source>jdbc/__default</jta-data-source>
 </persistence-unit>

So on all your environments you must ensure the JDBC resource has the same name (if you do not want to change the war file) but the actual config can be different, because it is stored in the Glassfish instance and not in your war file.

Answer 2

According to comments, as you asked @Trebor for determining DB type at runtime there is way to go through,visit this JDBC connection also

http://docs.oracle.com/javase/6/docs/api/java/sql/DatabaseMetaData.html

getClientInfo()

Entity Manager IN java

http://tomee.apache.org/examples-trunk/injection-of-entitymanager/README.html

this will definitely going to solve your issue .all the best .!