FirefoxDriver给出NullPointerException异常

Question

我试图运行Selenium测试为Maven构建一部分，所以我跟着这个文件中的配置：

http://www.gitshah.com/2010/10/how-to-run-selenium-tests-as-part-of.html

但试图运行我的测试类时：

public class LoginTest { 

    private WebDriver driver; 
    private String baseUrl; 
    private StringBuffer verificationErrors = new StringBuffer(); 

    @Before 
    public void setUp() throws Exception { 
     driver = new FirefoxDriver(); 
     baseUrl = "http://localhost:8080/"; 
    } 

    @Test 
    public void testLoginClass() throws Exception { 
     driver.get(baseUrl + "/MyApp/login"); 
     driver.findElement(By.id("j_username")).clear(); 
     driver.findElement(By.id("j_username")).sendKeys("1"); 
     driver.findElement(By.id("j_password")).clear(); 
     driver.findElement(By.id("j_password")).sendKeys("123456"); 
     driver.findElement(By.id("loginBtn")).click(); 
    } 

    @After 
    public void tearDown() throws Exception { 
     driver.quit(); 
     String verificationErrorString = verificationErrors.toString(); 
     if (!"".equals(verificationErrorString)) { 
      fail(verificationErrorString); 
     } 
    } 

} 

我在这行获得NullPointerException异常：

driver.get(baseUrl + "/MyApp/login"); 

请告诉我为什么我得到这个错误。

Answer 1

使测试类延伸后错误得以解决TestCase