How to resolve java.lang.NullPointerException in Page Object Model in Selenium? - selenium

Question

TestBase Class:-
public class TestBase {
public static WebDriver driver;
public static Properties prop;
// TestBase class constructor is used to initialize the properties object to
// fetch config variables from config.properties file.
public TestBase() {
try {
// File src = new File("./src/main/java/com/config/config.properties");
File src = new File(".\\src\\main\\java\\com\\config\\config.properties");
FileInputStream fs = new FileInputStream(src);
prop = new Properties();
prop.load(fs);
} catch (Exception e) {
e.printStackTrace();
}
}
public static void initialization() throws InterruptedException {
String browserName = prop.getProperty("Browser");
if (browserName.equals("chrome")) {
System.setProperty("webdriver.chrome.driver", "C:\\Selenium\\chromedriver_win32\\chromedriver.exe");
driver = new ChromeDriver();
} else {
System.out.println("Oops! Exception has Caught");
}
driver.manage().window().maximize();
driver.get(prop.getProperty("URL"));
}
}
HomePage Class:-
public class HomePage extends TestBase {
TestUtil testUtil;
#FindBy(xpath = "//a[#title='Update your profile, personal settings, and more']")
WebElement updateProfile;
#FindBy(xpath = "//a[#title='Create a New Post']")
WebElement createNewPost;
#FindBy(xpath="(//span[#class='count'])[2]")
WebElement drafts;
#FindBy(xpath="//a[#class='button masterbar__recent-drafts-see-all is-compact is-borderless']")
WebElement seeAll;
public HomePage() {
PageFactory.initElements(driver, this);
}
public ProfilePage updateYourProfile() throws AWTException, InterruptedException {
updateProfile.click();
Thread.sleep(3000);
return new ProfilePage();
}
public NewPostPage createNewPost() throws InterruptedException {
createNewPost.click();
Thread.sleep(3000);
return new NewPostPage();
}
public DraftsPage draftsPage() throws InterruptedException {
createNewPost.click();
Thread.sleep(3000);
drafts.click();
Thread.sleep(3000);
seeAll.click();
Thread.sleep(3000);
return new DraftsPage();
}
}
DraftsPage Class:-
public class DraftsPage extends TestBase {
#FindBy(xpath="(//button[#title='Toggle menu'])[1]")
WebElement toggleMenu;
#FindBy(xpath="(//button[#role='menuitem'])[2]")
WebElement trash;
public void toggleMenu() throws InterruptedException {
toggleMenu.click();
Thread.sleep(3000);
trash.click();
Thread.sleep(3000);
}
}
DraftsPageTest Class:-
public class DraftsPageTest extends TestBase {
ProfilePage myProfile;
LoginPage loginpage;
HomePage homepage;
NewPostPage newPostPage;
DraftsPage draftspage;
public DraftsPageTest() {
super();
}
#BeforeMethod
public void setUp() throws InterruptedException {
initialization();
loginpage = new LoginPage();
loginpage.login();
Thread.sleep(3000);
loginpage.userName(prop.getProperty("username"));
Thread.sleep(3000);
homepage = loginpage.password(prop.getProperty("password"));
Thread.sleep(3000);
myProfile = new ProfilePage();
Thread.sleep(3000);
newPostPage = new NewPostPage();
Thread.sleep(3000);
draftspage = new DraftsPage();
Thread.sleep(3000);
}
#Test
public void DraftsPageTest() throws InterruptedException {
homepage.draftsPage();
Thread.sleep(3000);
draftspage.toggleMenu();
Thread.sleep(3000);
}
#AfterMethod
public void close() {
driver.close();
}
}
Error Message:-
FAILED: DraftsPageTest
java.lang.NullPointerException
at com.pages.DraftsPage.toggleMenu(DraftsPage.java:18)
at com.testCases.DraftsPageTest.DraftsPageTest(DraftsPageTest.java:51)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:124)
at org.testng.internal.Invoker.invokeMethod(Invoker.java:583)
at org.testng.internal.Invoker.invokeTestMethod(Invoker.java:719)
at org.testng.internal.Invoker.invokeTestMethods(Invoker.java:989)
at org.testng.internal.TestMethodWorker.invokeTestMethods(TestMethodWorker.java:125)
at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:109)
at org.testng.TestRunner.privateRun(TestRunner.java:648)
at org.testng.TestRunner.run(TestRunner.java:505)
at org.testng.SuiteRunner.runTest(SuiteRunner.java:455)
at org.testng.SuiteRunner.runSequentially(SuiteRunner.java:450)
at org.testng.SuiteRunner.privateRun(SuiteRunner.java:415)
at org.testng.SuiteRunner.run(SuiteRunner.java:364)
at org.testng.SuiteRunnerWorker.runSuite(SuiteRunnerWorker.java:52)
at org.testng.SuiteRunnerWorker.run(SuiteRunnerWorker.java:84)
at org.testng.TestNG.runSuitesSequentially(TestNG.java:1208)
at org.testng.TestNG.runSuitesLocally(TestNG.java:1137)
at org.testng.TestNG.runSuites(TestNG.java:1049)
at org.testng.TestNG.run(TestNG.java:1017)
at org.testng.remote.AbstractRemoteTestNG.run(AbstractRemoteTestNG.java:114)
at org.testng.remote.RemoteTestNG.initAndRun(RemoteTestNG.java:251)
at org.testng.remote.RemoteTestNG.main(RemoteTestNG.java:77)
Description:-
I am trying to develop TestNG Framework with the help of Selenium.
I have developed HomePage, LoginPage, ProfilePage, NewPostPage, DraftsPage. While I was running the DraftsPageTest.java, #BeforeMethod was working fine
and the moment control comes to #Test, homepage.draftsPage(); is also working fine. But the moment control comes to draftspage.toggleMenu(); it is throwing
java.lang.NullPointerException.
Any help will be highly appreciated.
Thanks in advance:)

Answer 1

There's a bug in your code.
Please add a constructor which calls PageFactory.initElements(driver, this); to your com.pages.DraftsPage class [ similar to the HomePage constructor in your shared code ]. That should fix the problem.
The reason behind the NullPointerException is because, there's no call to PageFactory.initElements() the WebElement toggleMenu is not being initialised.