Java 配置失败：@AfterMethod拆卸

我是selenium webdriver的新手。 我试图在两个浏览器上运行Testng测试并行程序，但遭到了攻击，出现了以下错误。当你想跑的时候

package rough;


import org.testng.annotations.AfterMethod;
import org.testng.annotations.Optional;
import org.testng.annotations.Parameters;
import org.testng.annotations.Test;
import org.testng.annotations.BeforeMethod;
import org.testng.Assert;

import java.util.regex.Pattern;
import java.util.concurrent.TimeUnit;

import org.junit.*;

import static org.hamcrest.CoreMatchers.*;

import org.openqa.selenium.*;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.firefox.FirefoxDriver;
import org.openqa.selenium.ie.InternetExplorerDriver;
import org.openqa.selenium.support.ui.Select;

public class Browsers {
  private WebDriver driver;
  private String baseUrl;
  private boolean acceptNextAlert = true;
  private StringBuffer verificationErrors = new StringBuffer();

  @BeforeMethod
  public void tearDown1() throws Exception {
        System.out.println("Hello starting");
  }
  @Parameters("BROWSER")
public void setUp(@Optional String BROWSER) throws Exception {

    //To run test case parallely in different browsers
            if(BROWSER.equalsIgnoreCase("FF"))
            {
            //System.out.println(“Firefox driver would be used”);
            driver = new FirefoxDriver();
            }
            else
            if(BROWSER.equalsIgnoreCase("IE"))
            {
            //System.out.println(“Ie webdriver would be used”);
                System.setProperty("webdriver.ie.driver", "g:/Selenium Jar Files/IEDriverServer.exe");
            driver = new InternetExplorerDriver();
            }

   // driver = new FirefoxDriver();
    baseUrl = "http://book.theautomatedtester.co.uk/";
    driver.manage().timeouts().implicitlyWait(30, TimeUnit.SECONDS);
  }

  @Test
  public void test() throws Exception {
    driver.get(baseUrl + "/chapter1");
    driver.findElement(By.id("radiobutton")).click();
    new Select(driver.findElement(By.id("selecttype"))).selectByVisibleText("Selenium RC");
  }

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

  private boolean isElementPresent(By by) {
    try {
      driver.findElement(by);
      return true;
    } catch (NoSuchElementException e) {
      return false;
    }
  }

  private boolean isAlertPresent() {
    try {
      driver.switchTo().alert();
      return true;
    } catch (NoAlertPresentException e) {
      return false;
    }
  }

  private String closeAlertAndGetItsText() {
    try {
      Alert alert = driver.switchTo().alert();
      String alertText = alert.getText();
      if (acceptNextAlert) {
        alert.accept();
      } else {
        alert.dismiss();
      }
      return alertText;
    } finally {
      acceptNextAlert = true;
    }
  }
}

下面是XML

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE suite SYSTEM "http://testng.org/testng-1.0.dtd">
<suite name="Suite" parallel="True">
  <test name="Test">
  <parameter name = "BROWSER" value="FF"></parameter>
    <classes>
          <class name="rough.Browsers"/>
    </classes>
    <test name="Test">
    <parameter name = "BROWSER" value="IE"></parameter>
    <classes>
       <class name="rough.Browsers"/>
    </classes>
  </test> <!-- Test -->
</suite> <!-- Suite -->

---

请帮助我

真正的错误是

空点异常

。我猜在您的设置（或测试）中的某个地方，您抛出了一个错误，然后您尝试访问驱动程序，结果它是空的

---

在调用

driver.close（）

之前进行null检查，或者确保驱动程序从不为null（我更喜欢第一个选项）。

我收到了相同的错误。我的问题是，我试图在@afterMethod内说服司机。我关闭了司机而不是退出，问题得到了解决

我也面临同样的问题，为了解决这个问题，我将chromedriver更新到了我的系统中。实际上需要检查浏览器和浏览器驱动程序的兼容性

---

例如，如果我正在使用Chrome 74，那么我会更新我的驱动程序以支持Chrome 64。

非常好，您的猜测是正确的，当我调试时，驱动程序为空，非常感谢：）chromedriver 74

[TestNG] Running:
  C:\Users\Administrator\AppData\Local\Temp\testng-eclipse--757511090\testng-customsuite.xml

Hello starting
FAILED CONFIGURATION: @AfterMethod tearDown
java.lang.NullPointerException
    at rough.Browsers.tearDown(Browsers.java:65)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:84)
    at org.testng.internal.Invoker.invokeConfigurationMethod(Invoker.java:564)
    at org.testng.internal.Invoker.invokeConfigurations(Invoker.java:213)
    at org.testng.internal.Invoker.invokeMethod(Invoker.java:786)
    at org.testng.internal.Invoker.invokeTestMethod(Invoker.java:901)
    at org.testng.internal.Invoker.invokeTestMethods(Invoker.java:1231)
    at org.testng.internal.TestMethodWorker.invokeTestMethods(TestMethodWorker.java:127)
    at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:111)
    at org.testng.TestRunner.privateRun(TestRunner.java:767)
    at org.testng.TestRunner.run(TestRunner.java:617)
    at org.testng.SuiteRunner.runTest(SuiteRunner.java:334)
    at org.testng.SuiteRunner.runSequentially(SuiteRunner.java:329)
    at org.testng.SuiteRunner.privateRun(SuiteRunner.java:291)
    at org.testng.SuiteRunner.run(SuiteRunner.java:240)
    at org.testng.SuiteRunnerWorker.runSuite(SuiteRunnerWorker.java:52)
    at org.testng.SuiteRunnerWorker.run(SuiteRunnerWorker.java:86)
    at org.testng.TestNG.runSuitesSequentially(TestNG.java:1224)
    at org.testng.TestNG.runSuitesLocally(TestNG.java:1149)
    at org.testng.TestNG.run(TestNG.java:1057)
    at org.testng.remote.RemoteTestNG.run(RemoteTestNG.java:111)
    at org.testng.remote.RemoteTestNG.initAndRun(RemoteTestNG.java:204)
    at org.testng.remote.RemoteTestNG.main(RemoteTestNG.java:175)