How to run TestNG tests one-by-one - selenium

Question

I have a test suite and I want to run tests form XML file one-by-one. But when I'm running it, it runs all TCs at the same time (I have 3 open browsers at the same time).
My XML:
<suite name="TestingSuite" preserve-order="true" parallel="false" verbose="10">
<test name="Test1">
<classes>
<class name="guiAndFunctianal.LoginFail" />
<class name="guiAndFunctianal.LoginAsManager" />
<class name="guiAndFunctianal.CreateUserTest" />
</classes>
</test>
</suite>
My TCs looks like this:
public class LoginFail extends AbstractTest{
# BeforeTest
public void openBrowser() {
openBrowserFireFoxAllTcs();
}
# Test
public void main (){
}
# AfterTest
public void quit() {
driver.quit(); }
AbstractTest
public class AbstractTest {
WebDriver driver = new FirefoxDriver();
WebDriverWait wait = new WebDriverWait(driver, 10);
public void openBrowserFireFoxAllTcs() {
driver.get("some URL");
}

Answer 1

I assume you want sequential execution. Open a browser>finish testing>close browser and then repeat the same for other browsers. If that's case I would do the following:
TestNG.XML
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE suite SYSTEM "http://testng.org/testng-1.0.dtd">
<suite name="Suite" junit="false" parallel="false" configfailurepolicy="skip" thread-count="5" skipfailedinvocationcounts="false" data-provider-thread-count="10" group-by-instances="false" preserve-order="true" allow-return-values="false">
<test name="firefox" junit="false" skipfailedinvocationcounts="false" preserve-order="true" group-by-instances="false" allow-return-values="false">
<parameter name="browser" value="firefox" />
<classes>
<class name="com.github.tests.GitHubHomePageTests" />
</classes>
</test>
<test name="ie" junit="false" skipfailedinvocationcounts="false" preserve-order="true" group-by-instances="false" allow-return-values="false">
<parameter name="browser" value="ie" />
<classes>
<class name="com.github.tests.GitHubHomePageTests" />
</classes>
</test>
<test name="chrome" junit="false" skipfailedinvocationcounts="false" preserve-order="true" group-by-instances="false" allow-return-values="false">
<parameter name="browser" value="chrome" />
<classes>
<class name="com.github.tests.GitHubHomePageTests" />
</classes>
</test>
</suite>
How I instantiate the drivers:
package com.github.tests;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.firefox.FirefoxDriver;
import org.openqa.selenium.ie.InternetExplorerDriver;
import org.testng.annotations.*;
public class BaseTest {
public WebDriver driver;
String url = "https://github.com/";
#Parameters("browser")
#BeforeClass
public void SetUpTests(String browser) {
if (browser.equalsIgnoreCase("firefox")) {
driver = new FirefoxDriver();
} else if (browser.equalsIgnoreCase("ie")) {
System.setProperty("webdriver.ie.driver", ".\\drivers\\IEDriverServer.exe");
driver = new InternetExplorerDriver();
} else if (browser.equalsIgnoreCase("chrome")) {
System.setProperty("webdriver.chrome.driver", ".\\drivers\\chromedriver.exe");
driver = new ChromeDriver();
}
//Navigate to url
driver.navigate().to(url);
//Maximize the browser window
driver.manage().window().maximize();
}
#AfterClass
public void CleanUpDriver() throws Exception {
// Quit current driver instance.
try {
driver.quit();
} catch (Exception ex) {
throw ex;
}
}
How the test run
package com.github.tests;
import com.github.pageobjects.GitHubLandingPage;
import org.testng.Assert;
import org.testng.annotations.Test;
public class GitHubHomePageTests extends BaseTest {#Test
public void ExploreLinkTest() {
String explorePageTitle = new GitHubLandingPage(driver)
.clickGitHubExplorePage()
.getGitHubExplorerPageTitle().trim();
System.out.println(explorePageTitle);
Assert.assertEquals(explorePageTitle, "Explore GitHub");
}
}
A global Github repo is available here

Answer 2

Try this:
<suite name="TestingSuite" preserve-order="true" thread-count="1" verbose="10">
<test name="Test1">
<classes>
<class name="guiAndFunctianal.LoginFail" />
</classes>
</test>
<test name="Test2">
<classes>
<class name="guiAndFunctianal.LoginAsManager" />
</classes>
</test>
<test name="Test3">
<classes>
<class name="guiAndFunctianal.CreateUserTest" />
</classes>
</test>
</suite>

Answer 3

Close your driver before quit:
# AfterTest
public void quit() {
driver.close()
driver.quit();
}