code: public void initialize(Subject subject, CallbackHandler callbackHandler,
                             Map sharedState, Map options) {
          super.initialize(subject, callbackHandler, sharedState, options);
          Properties props = loadProperties((String) options.get("file"));
          initWithProps(props);
      }
docs: Read contents of the configured property file.
  
  @param subject
  @param callbackHandler
  @param sharedState
  @param options
  
  @see javax.security.auth.spi.LoginModule#initialize(javax.security.auth.Subject,
  javax.security.auth.callback.CallbackHandler, java.util.Map, java.util.Map)