Caused by: java.lang.illegalargumentexception: login module control flag is not available in the jaas config

Explanation of Error:

The error message “caused by: java.lang.illegalargumentexception: login module control flag is not available in the jaas config” is thrown when the specified login module control flag is not found in the Java Authentication and Authorization Service (JAAS) configuration.

Examples:

Let’s consider an example where we have a simple JAAS configuration file named “jaas.config” with the following content:

    
      Sample {
        com.example.SampleLoginModule required
        controlFlag="required";
      };
    
  

In the above configuration, we have specified the control flag as “required” for the “Sample” login module.

Now, if we try to authenticate using this configuration but specify an invalid control flag, such as “mandatory”, an IllegalArgumentException will be thrown with the error message mentioned.

    
      try {
        LoginContext loginContext = new LoginContext("Sample");
        loginContext.login();
      } catch (LoginException e) {
        Throwable cause = e.getCause();
        if (cause instanceof IllegalArgumentException) {
          System.out.println("Error: " + cause.getMessage());
        }
      }
    
  

The above code snippet tries to authenticate using the “Sample” login context. However, since we have an invalid control flag specified in the JAAS configuration file, the mentioned error will be displayed.