java.lang.NullPointerException when running a testcase via Selenium webDriver in Chrome

Question

There's my class that uses Selenium WebDriver and throws the error.

public class Test_Chromedriver {
    public static WebDriver driver; 
    public static void main(String[] args) {
        try {
System.setProperty("webdriver.chrome.driver","E:\\jars\\chromedriver.exe");
            WebDriver driver=new ChromeDriver();
            driver.get("http://www.facebook.com");
            driver.findElement(By.id("email")).sendKeys("surya");
            driver.findElement(By.name("pass")).sendKeys("hello");
        } catch (Exception e) {
            e.printStackTrace();
        }
        finally{
            driver.close();
            driver.quit();
        }
    }
}

once i ran the above code below Error Message is getting:

Started ChromeDriver
port=12877
version=23.0.1240.0
log=D:\Eclipse Juno Workspace\AS Selenium workspace\WebDriver Applications\chromedriver.log
Exception in thread "main" java.lang.NullPointerException
    at Test_Chromedriver.main(Test_Chromedriver.java:25)

Note: webdriver opening the chrome browser then entering the values into the fields, but above error is getting displayed all the times in console and finally block also not executing.

Answer 1

Your trouble come from your try/catch and specially your finally .

Because your driver is only localy in your try{} so... your finally can't do something with your driver. I'll rename your drivers to help you to see what happens here.

public class Test_Chromedriver {
    public static WebDriver driverNULL; // <- never instantiate
    public static void main(String[] args) {
        try {
            System.setProperty("webdriver.chrome.driver","E:\\jars\\chromedriver.exe");
            WebDriver driverOK=new ChromeDriver(); // < - local variable
            driverOK.get("http://www.facebook.com");
            driverOK.findElement(By.id("email")).sendKeys("surya");
            driverOK.findElement(By.name("pass")).sendKeys("hello");
        } catch (Exception e) {
            e.printStackTrace();
        }
        finally{
            driverNULL.close(); // <- want to close a object never instantiate so null pointer exception
            driverNULL.quit();
        }
    }
}

What can you do now ?

public class Test_Chromedriver {
    public static WebDriver driver; 
    public static void main(String[] args) {
        try {
            System.setProperty("webdriver.chrome.driver","E:\\jars\\chromedriver.exe");
            driver=new ChromeDriver(); // <- remove the Webdriver type
            driver.get("http://www.facebook.com");
            driver.findElement(By.id("email")).sendKeys("surya");
            driver.findElement(By.name("pass")).sendKeys("hello");
        } catch (Exception e) {
            e.printStackTrace();
        }
        finally{
            driver.close();
            driver.quit();
        }
    }
}

Answer 2

Maybe try to use TestNG and annotations?

http://testng.org/doc/index.html

They are making theirs work quite pretty good.

Using this type of structure will give you good head up for maintanence of tests and execution.

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;
import org.testng.annotations.AfterClass;
import org.testng.annotations.BeforeClass;
import org.testng.annotations.Test;

public class Test_Chromedriver {
    public static WebDriver driver; 


    @BeforeClass
    public void setUp(){
         System.setProperty("webdriver.chrome.driver","E:\\jars\\chromedriver.exe"");
         driver=new ChromeDriver();

}
   @Test 
    public static void TestFacebook() {
        try {
            driver.get("http://www.facebook.com");
            driver.findElement(By.id("email")).sendKeys("surya");
            driver.findElement(By.name("pass")).sendKeys("hello");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }



 @AfterClass
 public void tearDown(){
     driver.close();
     driver.quit();
 }

}