Selenium: Getting error with webElement or Webdriver "Drive" Variable

Question

New to automation. Help is greatly needed.

Why am I getting a NullPointerException?

Error: Null pointer access: The variable driver can only be null at this 
     location

Code:

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;
import org.testng.annotations.Test;
import common.controls.PageVerified;


public class Google extends PageVerified{
        PageVerified PgVerif = new PageVerified();
        WebDriver driver = new ChromeDriver();
    
        
        @Test
            public void Login() throws Exception{
            driver.manage().window().maximize();
            driver.get("https:Google.com");
            driver.findElement(By.xpath("//*[@id='lst-ib']")).sendKeys("Test");
            Thread.sleep(2000);
            driver.findElement(By.className("lsb")).click();
            PgVerif.Verify();
            String a = driver.getTitle();
            System.out.println(a);
            driver.findElement(By.xpath("//*[@id='lst-ib']")).clear();
            driver.findElement(By.xpath("//*[@id='lst-ib']")).sendKeys("Test");
            Thread.sleep(2000);
            driver.findElement(By.className("sbico-c")).click();
            String b = driver.getTitle();
            System.out.println(b);
            
            driver.close();
        }
            
        

Following is another class that I am calling where I get the error and it is in separate package than the above.

package common.controls;

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;

public class PageVerified 
{
    public String Verify()
        {
            WebDriver driver = null ;
            String pagetitle = driver.findElement(By.xpath("//*[@id='gb_70']")).getText();
                if(pagetitle != null)
                {
                    System.out.println(pagetitle + "Verified Successfully"  );
                    return pagetitle;
                }
                else
                {
                    System.out.println("Error::Not Verified");
                }
                return null;
        }   
}

Answer 1

You were getting null pointer exception because, though the driver is initialized in Google class.In this line PgVerif.Verify(); Control shifts to verify() method and in that method you are declaring another variable for driver (like WebDriver driver=null;). So a new variable driver is created (and this variable is not the previously initialized one from Google class).

So there are two things that you can do.

1. While creating the PageVerified instance you can send the initialized driver instance into its constructor and use it in the PageVerified class.

   public class Google
   {
     WebDriver driver = new ChromeDriver();
     PageVerified PgVerif = new PageVerified(driver);
   ...
   }
   
   public class PageVerified 
   {
    public WebDriver driver;
   
    public PageVerified(WebDriver driver)
    {
            this.driver = driver;
    }
   
    public String verify()
    {
       String pagetitle = driver.findElement(By.xpath("// [@id='gb_70']")).getText();
    ...
    }
   }
   

2. Send the initialized driver directly into the verify() method after initialization.

   public class Google
   {
     WebDriver driver = new ChromeDriver();
     PageVerified PgVerif = new PageVerified();
     ...
     PgVerif.verify(driver);
   }
   
   public class PageVerified 
   {
    public String verify(WebDriver driver)
    {
       String pagetitle = driver.findElement(By.xpath("// [@id='gb_70']")).getText();
          ...
    }
   }
   

Answer 2

You can try as per below: public WebDriver driver;

public BasePage(WebDriver driver) {

    PageFactory.initElements(driver, this);
    this.driver = driver;

}

public void verifyTitle(String etitle) {

    WebDriverWait wait = new WebDriverWait(driver, 10);
    try {
        wait.until(ExpectedConditions.titleIs(etitle));
        Reporter.log("Title is Matching: " + etitle, true);
    }

    catch (Exception e) {
        Reporter.log("Title is not Matching: " + etitle, true);
        Assert.fail();
    }
}