Class<? extends MongoTool> jobClass = (Class<? extends MongoTool>) Class.forName(className);
Configuration conf = BaseHadoopTest.getYarnCluster() != null
? new Configuration(BaseHadoopTest.getYarnCluster().getConfig())
: new Configuration();
MongoTool app = jobClass.getConstructor(new Class[]{Configuration.class})
.newInstance(conf);
ToolRunner.run(conf, app, cmd.toArray(new String[cmd.size()]));
}