To retry a failed test, add retryAnalyzer attribute with implemented class of 'RetryAnalyzerImpl.java' in @test annotation

RetryTest.java

import org.testng.Assert;
import org.testng.annotations.Test;

public class RetryTest {

	@Test(retryAnalyzer = RetryAnalyzerImpl.class)
	public void firstTest() {
		System.out.println("1");
		Assert.assertFalse(true);
	}

	@Test(retryAnalyzer = RetryAnalyzerImpl.class)
	public void secondTest() {
		System.out.println("2");
	}
}