Hi I am trying to run the below code with TestNG but all it gives me is java.lang.NullPointerException error. The Before method gets worked. After that, it shows the below error .What's going wrong. Please help!   ERROR :  java.lang.NullPointerException at lokbo.Login.afterMethod(Login.java:50) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)     at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)     at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)     at java.base/java.lang.reflect.Method.invoke(Unknown Source)     at org.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:108)     at org.testng.internal.Invoker.invokeConfigurationMethod(Invoker.java:523)     at org.testng.internal.Invoker.invokeConfigurations(Invoker.java:224)     at org.testng.internal.Invoker.invokeMethod(Invoker.java:731)     at org.testng.internal.Invoker.invokeTestMethod(Invoker.java:877)     at org.testng.internal.Invoker.invokeTestMethods(Invoker.java:1201)     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:776)     at org.testng.TestRunner.run(TestRunner.java:634)     at org.testng.SuiteRunner.runTest(SuiteRunner.java:425)     at org.testng.SuiteRunner.runSequentially(SuiteRunner.java:420)     at org.testng.SuiteRunner.privateRun(SuiteRunner.java:385)     at org.testng.SuiteRunner.run(SuiteRunner.java:334)     at org.testng.SuiteRunnerWorker.runSuite(SuiteRunnerWorker.java:52)     at org.testng.SuiteRunnerWorker.run(SuiteRunnerWorker.java:86)     at org.testng.TestNG.runSuitesSequentially(TestNG.java:1318)     at org.testng.TestNG.runSuitesLocally(TestNG.java:1243)     at org.testng.TestNG.runSuites(TestNG.java:1161)     at org.testng.TestNG.run(TestNG.java:1129)     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)   Code :    package lokbo;  import java.util.concurrent.TimeUnit;  import org.testng.annotations.Test;   import org.openqa.selenium.By;  import org.openqa.selenium.WebDriver;  import org.openqa.selenium.chrome.ChromeDriver;  import org.testng.annotations.AfterMethod;   import org.testng.annotations.BeforeMethod;     public class Login  {   public  WebDriver driver;   @BeforeMethod  public void beforeMethod()  {  System.setProperty("webdriver.chrome.driver", "E:\\RF   AUTOMATION\\chromedriver_win32\\chromedriver.exe");     WebDriver driver=new ChromeDriver();     String baseurl= "http://dev.idrottonline.se/";     driver.get(baseurl);     driver.manage().timeouts().implicitlyWait(300, TimeUnit.SECONDS);       String expectedTitle = "Idrottonline2 - Svenskidrott";     String actualTitle="";     actualTitle=driver.getTitle();     if(actualTitle.contentEquals(expectedTitle))     //if(expectedTitle.isDisplayed())        {         System.out.println("Test pass");     }     else     {         System.out.println("Test Fail");     } }   @Test   public void login() {    driver.findElement(By.id("IdrottOnline-LoginBoxTarget")).click();     driver.findElement(By.id("ioui-access-username")).sendKeys("lagorf01");     driver.findElement(By.id("ioui-access-password")).sendKeys("Dumbo753");     driver.findElement(By.xpath(".//*[@id='ioui-access-login']/fieldset/div[5]/div/button")).click();  }  @AfterMethod  public void afterMethod() {   driver.manage().deleteAllCookies();   driver.quit(); }  }
What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?
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