java.lang.NullPointerException occured while implementing driver initialization through inheritance

Question

Base class:

public class Base {

  public WebDriver driver ;

   @BeforeMethod
  public void initialize() {
     System.setProperty("webdriver.chrome.driver", "/Users/apple/eclipse-workspace/Selenium/src/Google/chromedriver");

    ChromeDriver driver = new ChromeDriver() ;
    driver.manage().window().maximize();

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

   @AfterMethod
   public void exitdriver() {
      driver.close();
   }
}

Page Class:

public class Pages {

  WebDriver driver ;

   public Pages( WebDriver driver)
   {
        this.driver = driver ;
   }

    @FindBy(how = How.XPATH, using = ".//*[@id='lst-ib']")
    WebElement search ;

    public void Googletext() throws InterruptedException
    {
        search.sendKeys("Test");
    }
}

Main Class

 public class Front extends Base {


  @Test
  public void Login() throws InterruptedException {

      Pages PagesObj = new Pages(driver);
      PagesObj.Googletext();  
  }
}

Answer 1

You were getting NullpointerException because you are declaring another ChromeDriver instance inside the initialize() method and creating an instance of ChromeDriver object whose scope is limited to initialize() method itself.

Make the following corrections in the code:

In Base class:

public void initialize() {
 ..some code

  driver = new ChromeDriver() ;

..some code 
}

And you don't need another WebDriver driver declaration in Front class.( you can remove it).

In Front class:

public class Front extends Base {

  @Test
  public void Login() throws InterruptedException {
      Pages PagesObj = new Pages(driver);
      PagesObj.Googletext();  
  }
}

So, now the driver gets initialized in initialize() method of Base class and the same driver instance is passed through to your Page object.