Customizing Bluemix's jndiName when it is automatically configured

Question

IBM Bluexmix automatically configures bound services(https://console.ng.bluemix.net/docs/runtimes/liberty/autoConfig.html)

This results in having dataSource entry in the server.xml (https://console.ng.bluemix.net/docs/services/SQLDB/index.html#SQLDB). It looks like this:

<dataSource id='db2-mydb' jdbcDriverRef='db2-driver' jndiName='jdbc/mydb'
         statementCacheSize='30' transactional='true'>
    <properties.db2.jcc databaseName='${cloud.services.mydb.connection.db}' 
           id='db2-mydb-props' 
           password='${cloud.services.mydb.connection.password}' 
           portNumber='${cloud.services.mydb.connection.port}' 
           serverName='${cloud.services.mydb.connection.host}' 
           user='${cloud.services.mydb.connection.username}'/> 
</dataSource>    

The jndiName is jdbs/DBServiceName. I want to customize the jndiName so that I can use it in the application without knowing the db service name. At the same time I also want blueMix to create the properties for me because I don't know the db service name before pushing the code.

EDIT Clarifying the setup on BlueMix

• We have a space which contains DB2
• We have a test space
• In test space we have two applications app1 and app2
• In the test space we create two user provided service instances, and pass in DB2 credentials to them. We name them DB1 and DB2
• We bind DB1 to app1 and DB2 to app2
• When we push the code the jdndiName is automatically configured to jdbc/DB1 and jdbc/DB2
• we want to reference that name in persistence.xml, and want to have control over that name. Or somehow read the service name in persistence.xml

Answer 1

You don't necessarily need to know the JNDI name to be able to use the resource in the application. The Liberty buildpack is doing the auto-configuration, but there is also a Liberty feature cloudAutowiring-1.0 that will help you look up the resources if there is only one corresponding instance of the service bound to the app.

Check out these two sample apps:

• https://github.com/IBM-Bluemix/java-datacache/blob/master/src/com/ibm/cloudoe/ecaas/samples/ECaaSSample.java#L35
• https://github.com/IBM-Bluemix/java-db/blob/master/src/main/java/example/jpa/TODOListResource.java#L183