1. In the WebSphere admin console, expand Resources > JDBC or Resoruces > JMS.
2. Select any resource.
3. Select JAAS - J2C authentication data.
4. Select New.
5. Give the J2C alias a name and define the username and password. Select OK.
6. Select Save.

In this example, a J2C alias named mySQL is created.

On the WebSphere server, the J2C aliases you've created will be in the ${WAS_INSTALL_ROOT}/profiles/dmgr_profile/config/cells/your_cell/security.xml file. The security.xml file will contain something like this.

<authDataEntries 
  xmi:id="JAASAuthData_1478117720103"
  alias="john.doe"
  userId="john.doe"
  password="{xor}OttvApas44jkrAa="
  description="J2C alias for john.doe"
/>

IBM WebSphere - JDBC data source and J2C alias

Configure a Java app to use a JDBC

Connect to a SQL database via DataSource

Connect to a SQL database via DriverManager

At Monitoring and Tuning > Performance Viewer > Current activity > your application server > Summary Reports > JDBC Connection Pools > your JDBC provider > your JNDI, the connection count should be 1 for the single connection to the database.