Question

我是Selenium WebDriver的新手。一段java.lang.NullPointerException一直困扰着我，我无法理解为什么。以下是我的课程，实际上非常简单：

suiteBase.java

package utilities.suiteBase;

import org.openqa.selenium.WebDriver;

import actions.testPage1.testPage1Actions;
import ui_map.testPage1.TestPage1UI;

public class suiteBase {
    public WebDriver driver;

    protected static TestPage1UI tpui = new TestPage1UI();
    protected static testPage1Actions tpa = new testPage1Actions();
}

testPage1Actions.java

package actions.testPage1;

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebDriver.Timeouts;
import org.openqa.selenium.WebElement;

import utilities.suiteBase.suiteBase;

public class testPage1Actions extends suiteBase {

    public WebDriver driver;
    public void test(WebDriver driver){
        WebElement loc1 = driver.findElement(By.xpath("id('email')"));
        loc1.sendKeys("testing");
        System.out.println("done...");  
    }    
}

TestPage1.java

package testPage1;

import org.openqa.selenium.WebDriver;
import org.testng.annotations.Parameters;
import org.testng.annotations.Test;

import utilities.suiteBase.BrowserOpen;

import utilities.suiteBase.suiteBase;

public class TestPage1 extends suiteBase{
    public WebDriver driver;
    BrowserOpen browse = new BrowserOpen();

    @Parameters({ "browserType", "appURL" })
    @Test(priority = 1)
    public void openBrowser(String browserType,  String appURL){
        browse.setUp(browserType, appURL);  
        System.out.println("Done....");
    }

    @Test(priority = 2)
    public void testCase1() throws InterruptedException{
        driver.wait(1000);
        tpa.test(driver);           
    }
}

我使用XML运行TestPage1.java文件，遇到以下错误：

java.lang.NullPointerException at testPage1.TestPage1.testCase1（TestPage1.java:28）at sun.reflect.NativeMethodAccessorImpl.invoke0（Native Method）at sun.reflect.NativeMethodAccessorImpl.invoke（NativeMethodAccessorImpl.java:62）在 sun.reflect.DelegatingMethodAccessorImpl.invoke（DelegatingMethodAccessorImpl.java:43）在java.lang.reflect.Method.invoke（Method.java:497）at org.testng.internal.MethodInvocationHelper.invokeMethod（MethodInvocationHelper.java:80）在org.testng.internal.Invoker.invokeMethod（Invoker.java:714）at org.testng.internal.Invoker.invokeTestMethod（Invoker.java:901）at at org.testng.internal.Invoker.invokeTestMethods（Invoker.java:1231）at at org.testng.internal.TestMethodWorker.invokeTestMethods（TestMethodWorker.java:127）在 org.testng.internal.TestMethodWorker.run（TestMethodWorker.java:111）在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 at org.testng.SuiteRunner.privateRun（SuiteRunner.java：291）at 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:1198）at at org.testng.TestNG.runSuitesLocally（TestNG.java:1123）at at org.testng.TestNG.run（TestNG.java:1031）at org.testng.remote.AbstractRemoteTestNG.run（AbstractRemoteTestNG.java:126）在org.testng.remote.RemoteTestNG.initAndRun（RemoteTestNG.java:137）在org.testng.remote.RemoteTestNG.main（RemoteTestNG.java:58）

我还有一个在TestPage1之前运行的browserOpen类，其中我声明了WebDriver

package utilities.suiteBase;

import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.firefox.FirefoxDriver;
import org.testng.annotations.AfterClass;
import org.testng.annotations.BeforeClass;
import org.testng.annotations.Parameters;
import org.testng.annotations.Test;

import utilities.suiteBase.BrowserOpen;

public class BrowserOpen {

    public WebDriver driver;
    static String driverPath = "E:\\Selenium\\";

    public void setUp(String browserType, String appURL) {
        try {
            setDriver(browserType, appURL);

        } catch (Exception e) {
            System.out.println("Error....." + e.getStackTrace());
        }
    }

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

private void setDriver(String browserType, String appURL) {
    switch (browserType) {
    case "chrome":
        driver = initChromeDriver(appURL);
        break;
    case "firefox":
        driver = initFirefoxDriver(appURL);
        break;
    default:
        System.out.println("browser : " + browserType
                + " is invalid, Launching Firefox as browser of choice..");
        driver = initFirefoxDriver(appURL);
    }
}

private static WebDriver initChromeDriver(String appURL) {
    System.out.println("Launching google chrome with new profile..");
    System.setProperty("webdriver.chrome.driver", driverPath + "chromedriver.exe");
    WebDriver driver = new ChromeDriver();
    driver.manage().window().maximize();
    driver.navigate().to(appURL);
    System.out.println("URL inserted");
//  driver.get(appURL);
    return driver;
}

private static WebDriver initFirefoxDriver(String appURL) {
    System.out.println("Launching Firefox browser..");
    WebDriver driver = new FirefoxDriver();
    driver.manage().window().maximize();
    driver.navigate().to(appURL);
    return driver;
}
}

Answer 1

我之前从未使用过这项技术，但我看不到这些技术。

WebDriver driver = new FirefoxDriver();

WebDriver未初始化您需要在使用之前初始化它们。像：

$app->get('/myownurl', MyController::class);

或者别的什么。看看这个：http://www.seleniumhq.org/docs/03_webdriver.jsp

- UPD：异常可能抛出testCase1（）tpa.test（WebDriver）。 tpa可能为空。

Answer 2

您正在使用来自testng.xml文件的TestPage1类中的@Parameters（{＆＃34; browserType＆＃34;，＆＃34; appURL＆＃34;}）。希望您使用此xml文件来运行测试。

Answer 3

当我声明-公共静态WebDriver驱动程序时； @BeforeSuite之前

，然后在方法中，如果我们再次声明为

WebDriver driver = new FirefoxDriver();

并运行脚本，然后向我显示java.lang.NullPointerException错误。

请尝试以下代码解决：-

driver = new Firefoxdriver();

示例-

public class LearnCheckBox {
    
    public static WebDriver driver;
    
    @BeforeSuite
    
    public static void verify_SetupBrowser() throws InterruptedException
    {
        driver = new FirefoxDriver(); // 
        driver.get("https://learn.letskodeit.com/p/practice");
        driver.manage().window().maximize();
        Thread.sleep(2000);
    }

Ashish Bind

获取selenium webdriver类

suiteBase.java

testPage1Actions.java

TestPage1.java

3 个答案: