How to solve java.lang.NullPointerException error in button click event?

Question

I'm using Java,Selenium web driver and TestNG framework. I have a method to click a button in web page. But it didn't work. When debugging I could find xpath is not passed to the button. Then I tried giving xpath in the same place where click event is called using driver.findElement(By.xpath.....). It worked without any error. I have included my codes below. Please check and help me to solve this problem.

ClickNewButton(); 
// Method body 
public void ClickNewButton() {click(NewButton);} 
@FindBy(xpath = Locators.newButton) // In this place newButton has it's xpath
WebElement NewButton; // Here NewButtton doesn't contain any xpath. It's null (This is where problem occurs exactly)
// Xpath in Locators class
public static final String newButton = "html/body/div[2]/div[2]/div/div[2]/div/div[1]/div[3]/div[2]/div[1]/div/div[2]/div/div[3]/div/div[2]/button"; 
// click method's body in Base class
public void click(WebElement webElement) {
 webElement.click();
}

Please note that first three code segments are in same class and that class is extended from Base class

• sameer joshi: please share your html file
• Syrus: @sameer, I don't think that it's possible. But I can confirm there is nothing wrong with the xpath. I've tested it.
• Sachintha: Did you try with some wait time?
• Sachintha: give xpath like below and try @FindBy(xpath = "your xpath") private WebElement btnSubmit;
• Syrus: I guess you are talking about a scenario of element is not found. If it's so , I didn't use wait but I have tried sleep method to wait until the interface loads properly. Seems to be that's not the problem

Answer 1

I found the solution to the problem. I just had to add single line of code to make this work.

MyClass object= PageFactory.initElements(driver, MyClass.class); 

I had to add this code to the class where I was creating the test and tried. It worked. The Error wasn't in using of @FindBy. So I guess this will help someone in the future.

Answer 2

Use JavascriptExecutor -

JavascriptExecutor js = (JavascriptExecutor)driver;
js.executeScript("arguments[0].click();", yourLoginButton);

• demouser123: Why do you think this is going to solve Null Pointer Exception? The question is about solving the NPE and not how you can achieve this using other method.

Answer 3

I think the line which is causing the problem may be

@FindBy(xpath = Locators.newButton)

You are directly calling an element from the Locators class, right?

Try creating an object of Locators class in the Class where you are using the @FindBy.

I may not be correct because the flow that you are given in the question is not enough for finding the solution.

Answer 4

package org.com;
import java.util.concurrent.TimeUnit;
import org.openqa.selenium.By;
import org.openqa.selenium.JavascriptExecutor;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.chrome.ChromeDriver;
import org.testng.annotations.Test;
import io.cucumber.java.After;
import io.cucumber.java.Before;
public class ASOS {
 
 WebDriver driver;
 
 
 @Test()
 public void login() {
 System.setProperty("webdriver.chrome.driver","C:\\Users\\Raja\\eclipse-workspace\\FebrevisionTask\\Driver\\chromedriver.exe");
 driver=new ChromeDriver();
 driver.get("https://www.amazon.in/ref=nav_logo");
 driver.manage().window().maximize();
 // driver.manage().timeouts().implicitlyWait(300, TimeUnit.SECONDS);
 WebElement txtUserName=driver.findElement(By.xpath("//a[@href='/deals?ref_=nav_cs_gb']"));
 txtUserName.click();
 
 }
 
 @Test()
 public void TodayDealsPage() throws InterruptedException {
 
 
 Thread.sleep(2000);
 
// JavascriptExecutor executor = (JavascriptExecutor)driver;
// executor.executeScript("window.scroll(0,450)","");
 
 JavascriptExecutor js1 = (JavascriptExecutor) driver;
 js1.executeScript("window.scrollBy(0, 450)",""); 
 
 Thread.sleep(3000);
 
 WebElement laptop = driver.findElement(By.xpath("//div[text()='Top Offers on Laptops & Desktops; Upto INR 40000 Off']"));
 laptop.click();
 
 
 }
 
 }
 

• Lee Jensen: Welcome to the community! It would be helpful to add an explanation to your code on how this solves the problem.