@Override
  public Stage createNew(long requestId,
                         @Assisted("logDir") String logDir,
                         @Assisted("clusterName") String clusterName,
                         @Assisted("clusterId") long clusterId,
                         @Assisted("requestContext") String requestContext,
                         @Assisted("commandParamsStage") String commandParamsStage,
                         @Assisted("hostParamsStage") String hostParamsStage) {
    return new Stage(requestId, logDir, clusterName, clusterId, requestContext, commandParamsStage, hostParamsStage,
        injector.getInstance(HostRoleCommandFactory.class),
        injector.getInstance(ExecutionCommandWrapperFactory.class));
  }
Constructor via the factory.
@param requestId Unique identifier for the request
@param logDir Directory to log to
@param clusterName Cluster name
@param clusterId Cluster ID
@param requestContext Information about the context of the request
@param commandParamsStage Information about the command parameters
@param hostParamsStage Information about the host parameters for the stage
@return An instance of a Stage with the provided params.
ambari-server/src/main/java/org/apache/ambari/server/actionmanager/StageFactoryImpl.java