code: public void onResourceLaunched(final ResourceLaunchEvent resourceLaunchEvent,
                                   final String command,
                                   final String evaluatorConfigurationString) {
      final String resourceId = resourceLaunchEvent.getIdentifier();
  
      if (this.failedResources.containsKey(resourceId)) {
        LOG.log(Level.FINE, "ResourceLaunch event triggered on a failed container. " +
            "Notifying REEF of failed container.");
        CloudTask cloudTask = this.failedResources.get(resourceId);
        this.onAzureBatchTaskStatus(cloudTask);
      } else if (this.evaluators.get(resourceId).isPresent()) {
        LOG.log(Level.FINE, "Preparing to launch resourceId = {0}", resourceId);
        this.launchEvaluator(resourceLaunchEvent, command, evaluatorConfigurationString);
      } else {
        LOG.log(Level.WARNING, "Received a ResourceLaunch event for an unknown resourceId = {0}", resourceId);
      }
  
      this.updateRuntimeStatus();
    }
docs: Event handler method for {@link ResourceLaunchEvent}. This method will determine if the evaluator shim
  is online and send the evaluator launch command to the shim to start the evaluator.
  
  @param resourceLaunchEvent an instance of {@ResourceLaunchEvent}
  @param command OS command to launch the evaluator process.
  @param evaluatorConfigurationString evaluator configuration serialized as a String.