Deployment Common Exception

weblogic.common.ResourceException: java.security.PrivilegedActionException: weblogic.common.ResourceException: java.security.PrivilegedActionException: weblogic.common.ResourceException: No credential mapper 

what does  Auto Generate and Synchronize weblogic-jdbc.xml Descriptors do?
When this field is selected, this means that your deployed application will not use global data sources on the server as the following

   why this exception happen?

Because the web logic will expect that data source is not global and will check             it's name with JDNI to get it's credentials and will not find it decleared before on weblogic server, so it will throw this   exception to informs you what happen with JDNI.  

When to Enable Global Transactions in a Data Source?

If your applications or environment meet any of the following criteria, you should enable global transactions in the Data Source (select Honor Global Transactions during configuration). This creates a Tx Data Source in the config.xml file.

• Use the Java Transaction API (JTA)
• Use the EJB container in WebLogic Server to manage transactions
• Include multiple database updates within a single transaction
• Access multiple resources, such as a database and the Java Messaging Service (JMS), during a transaction
• Use the same connection pool on multiple servers

When not to enable global transactions?

• The underlying connection pool uses a non-XA JDBC driver
• You don't plan to use distributed transactions in your applications.
• You plan to use database definition language (DDL) SQL commands through this data source (only applies to some DBMSs or JDBC drivers).

solution of the issue:-

• R-click on your application and select properties
  
  
   

• ٍSelect Deployement then weblogic
  

• un-check auto generate and synchronize weblogic JDBC descriptors
• click ok then start in your deployement process again the previous exception will not appear any more.