WebDriver TestNG example

public class GmailTestCases {

  @BeforeMethod
public void launch() {
driver= new FirefoxDriver();
  driver.get("http://gmail.com");
driver.manage().timeouts().implicitlyWait(10, TimeUnit.SECONDS);
}

@AfterMethod
public void quit() {
driver.quit();
}


@Test
public void verifyLoginPage() {

String actual_title = driver.getTitle();
String expected_title = "Gmail: Email from Google";
Assert.assertEquals(expected_title, actual_title);
}


@Test
public void verifyLoginWithValidCredentials() throws Exception
{
driver.findElement(By.id("Email")).sendKeys("test@gmail.com");
driver.findElement(By.id("Passwd")).sendKeys("validpassword");
driver.findElement(By.id("signIn")).click();
Thread.sleep(10000);
String expected_username = "Test user";
String actual_username   = driver.findElement(By.id("gbi4t")).getText();
Assert.assertEquals(expected_username, actual_username);
}



@Test
public void verifyLoginWithInValidCredentials() throws InterruptedException {
driver.findElement(By.id("Email")).sendKeys("test@gmail.com");
driver.findElement(By.id("Passwd")).sendKeys("invalidpwd");
driver.findElement(By.id("signIn")).click();
Thread.sleep(10000);
                Assert.assertTrue(driver.getPageSource().contains("The username or password you entered is incorrect"));
}

@Test
public void verifyLinks() throws InterruptedException {

List <WebElement> alllinks = driver.findElements(By.tagName("a"));

for(int i=0;i<alllinks.size();i++) {
System.out.println(alllinks.get(i).getText());
}

for(int i=0;i<alllinks.size();i++){

alllinks = driver.findElements(By.tagName("a"));
alllinks.get(i).click();
Thread.sleep(1000);
driver.navigate().to("http://gmail.com");
Thread.sleep(1000);
}
}

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XML file

<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE suite SYSTEM "http://testng.org/testng-1.0.dtd"> <!-- Specify the test suite name --> <suite name="Gmail_Login" verbose="1" annotations="JDK"> <!-- Specify the test name --> <test name="gmail_Login_Scenarios" preserve-order="true"> <classes> <class name="packagename.GmailTestCases"> <methods> <include name="verifyLoginPage" /> <include name="verifyLoginWithValidCredentials" /> <include name="verifyLoginWithInValidCredentials" /> <include name="verifyLinks" /> </methods> </class> </classes> </test> </suite>