When I run as TestNG, it's throwing Exception in thread main, but is running fine if it's ran as java application

Question

I'm trying to run a basic TestNG class, but I'm getting this exception Exception in thread "main" com.beust.jcommander.ParameterException: Was passed main parameter '-d' but no main parameter was defined in your arg class

If I give main() and try with run as a java application, it's launching the browser fine. But when I run as TestNG, it's throwing Exception. I tried adding jcommander.jar manually and even tried with update maven project.

@Test
public void checking()

{
    System.setProperty("webdriver.chrome.driver", "./driver/chromedriver");

    ChromeDriver driver = new ChromeDriver();

    driver.manage().window().maximize();

    driver.get("https://www.google.com");
}

}

I expect the browser has to launch and load google.com, but I'm getting Exception in thread "main" com.beust.jcommander.ParameterException: Was passed main parameter '-d' but no main parameter was defined in your arg class

at com.beust.jcommander.JCommander.initMainParameterValue(JCommander.java:936)
at com.beust.jcommander.JCommander.parseValues(JCommander.java:752)
at com.beust.jcommander.JCommander.parse(JCommander.java:340)
at com.beust.jcommander.JCommander.parse(JCommander.java:319)
at com.beust.jcommander.JCommander.<init>(JCommander.java:253)
at org.testng.remote.RemoteTestNG.main(RemoteTestNG.java:44)

Answer 1

check whether testng installed successfully and jars have been added properly in maven