问题描述
我有两个单独的Selenium Webdriver类.我创建的第一个类没有任何错误，但第二个类抛出NullPointerException.
错误指出波纹管WebDriverWait wait = new WebDriverWait(driver,40);.如果在一行代码中实例化了driver，则不仅会为WebDriverWait抛出NullPointer异常.例如Actions action = new Actions(driver);.
NullPointerException也引发上面的代码.但是头等舱没有这类问题.
I have two separated Selenium Webdriver's classes. The class I made first runs without any error but the second class throws the NullPointerException.
The error points out the bellow line WebDriverWait wait = new WebDriverWait(driver,40);. not only for the WebDriverWait the NullPointer exception throws if driver is instantiated in a line of code. eg Actions action = new Actions(driver);.
The NullPointerException throws on the above code also. But the the first class doesn't have kind of issue.
我第一次上课
package Initiate;
import dataProvider.CommonClass;
import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.interactions.Actions;
import org.openqa.selenium.support.ui.ExpectedConditions;
import org.openqa.selenium.support.ui.WebDriverWait;
import java.util.concurrent.TimeUnit;
public class NewBOM {
public WebDriver driver;
By newBomButton = By.id("btnUpdate");
public NewBOM(WebDriver driver){
this.driver=driver;
this.CreateNewBOM();
}
public void CreateNewBOM(){
Actions action = new Actions(driver);
WebDriverWait wait = new WebDriverWait(driver, 40);
wait.pollingEvery(2, TimeUnit.SECONDS);
WebElement newBomBtn = driver.findElement(newBomButton);
wait.until(ExpectedConditions.elementToBeClickable(newBomBtn));
action.moveToElement(newBomBtn).click().build().perform();
}
}
第二个引发nullpointer异常的类
The second class which throws the nullpointer exception
package Initiate;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.support.ui.WebDriverWait;
public class NewBOO {
public WebDriver driver;
public NewBOO(WebDriver driver){
this.driver=driver;
}
public void test() throws InterruptedException {
WebDriverWait wait = new WebDriverWait(driver,40);
System.out.println("Test print");
}
}
我第一次上课的TestNg课
TestNg class for the class I made 1st
import Initiate.NewBOM;
import org.junit.BeforeClass;
import org.openqa.selenium.WebDriver;
import org.testng.annotations.Test;
public class CreateBOM {
public WebDriver driver;
private NewBOM objNewBOM;
@Test(priority = 1)
public void clickOnNewBOMButton(){
objNewBOM = new NewBOM(driver);
objNewBOM.CreateNewBOM();
}
}
我第二次上课的TestNg课
TestNg class for the class I made 2nd
import Initiate.NewBOO;
import org.openqa.selenium.WebDriver;
import org.testng.annotations.Test;
public class CreateBOO {
public WebDriver driver;
NewBOO objNewBOO;
@Test(priority = 1)
public void temporyTest() throws InterruptedException {
objNewBOO = new NewBOO(driver);
objNewBOO.test();
}
}
完整的错误消息
java.lang.NullPointerException
at com.google.common.base.Preconditions.checkNotNull(Preconditions.java:787)
at org.openqa.selenium.support.ui.FluentWait.<init>(FluentWait.java:96)
at org.openqa.selenium.support.ui.WebDriverWait.<init>(WebDriverWait.java:71)
at org.openqa.selenium.support.ui.WebDriverWait.<init>(WebDriverWait.java:45)
at Initiate.NewBOO.test(NewBOO.java:17)
at CreateBOO.temporyTest(CreateBOO.java:11)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:108)
at org.testng.internal.Invoker.invokeMethod(Invoker.java:661)
at org.testng.internal.Invoker.invokeTestMethod(Invoker.java:869)
at org.testng.internal.Invoker.invokeTestMethods(Invoker.java:1193)
at org.testng.internal.TestMethodWorker.invokeTestMethods(TestMethodWorker.java:126)
at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:109)
at org.testng.TestRunner.privateRun(TestRunner.java:744)
at org.testng.TestRunner.run(TestRunner.java:602)
at org.testng.SuiteRunner.runTest(SuiteRunner.java:380)
at org.testng.SuiteRunner.runSequentially(SuiteRunner.java:375)
at org.testng.SuiteRunner.privateRun(SuiteRunner.java:340)
at org.testng.SuiteRunner.run(SuiteRunner.java:289)
at org.testng.SuiteRunnerWorker.runSuite(SuiteRunnerWorker.java:52)
at org.testng.SuiteRunnerWorker.run(SuiteRunnerWorker.java:86)
at org.testng.TestNG.runSuitesSequentially(TestNG.java:1301)
at org.testng.TestNG.runSuitesLocally(TestNG.java:1226)
at org.testng.TestNG.runSuites(TestNG.java:1144)
at org.testng.TestNG.run(TestNG.java:1115)
at org.testng.IDEARemoteTestNG.run(IDEARemoteTestNG.java:72)
at org.testng.RemoteTestNGStarter.main(RemoteTestNGStarter.java:123)
===============================================
Default Suite`enter code here`
Total tests run: 1, Failures: 1, Skips: 0
===============================================
Process finished with exit code 0
我分别测试了两个testNg类，并且两个类都是独立的.但是第一个类不运行任何空指针异常，而第二个类则抛出空指针异常.
I test both testNg classes individually and both classes are independent. But 1st class runs wothout any null pointer exception and 2nd class throws a nullpointer exception.
推荐答案
您的代码似乎没有初始化WebDriver并尝试使用它，因此它抛出了NullPointerException.在TestNG中，可以使用@ BeforeSuite，@ BeforeTest，@ BeforeClass来初始化依赖项.下面的示例显示了如何在'BeforeClass'中初始化Webdriver.
It looks like your code didn't init WebDriver and try to use it, so it throws the NullPointerException.In TestNG, you can use @BeforeSuite, @BeforeTest, @BeforeClass to initialize your dependencies. The example below shows how to init the webdriver in 'BeforeClass'.
import Initiate.NewBOM;
import org.junit.BeforeClass;
import org.openqa.selenium.WebDriver;
import org.testng.annotations.Test;
public class CreateBOM {
public WebDriver driver;
private NewBOM objNewBOM;
@BeforeClass
public void setupClass(){
driver = new FirefoxDriver();
}
@Test(priority = 1)
public void clickOnNewBOMButton(){
objNewBOM = new NewBOM(driver);
objNewBOM.CreateNewBOM();
}
}
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