Java 初始化一个 webdriver 实例
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initialize a webdriver instance
提问by Mrunal Gosar
Hi i have a global class as belows:
嗨，我有一个全局类，如下所示：
public class Global
{
public WebDriver driver=null;
public WebDriverWait wait=null;
public Global()
{
BrowserInitializer obj=new BrowserInitializer();
obj.initialize();
}
}
I have another class called browser initializer where i want to initialize the driver instance to firefox as below:
我有另一个名为浏览器初始化程序的类，我想在其中将驱动程序实例初始化为 firefox，如下所示：
public class BrowserInitializer extends Global
{
public void initialize()
{
driver=new FirefoxDriver();
driver.manage().window().maximize();
wait=new WebDriverWait(driver, 5000);
}
}
I have testNG class where i want to run some test as belows :
我有 testNG 类，我想在其中运行一些测试，如下所示：
public class TestNG1
{
Global globalObj=new Global();
@Test
public void login()
{
globalObj.driver.get("someURL");
globalObj.driver.findElement(By.id("someid")).sendKeys("someusername");
globalObj.driver.findElement(By.id("someid")).sendKeys("somepassword");
globalObj.driver.findElement(By.id("someid")).submit();
}
}
Now i am getting error like :
现在我收到如下错误：
org.testng.TestNGException:
Cannot instantiate class unitTest.myTest.TestNG1
at org.testng.internal.ObjectFactoryImpl.newInstance(ObjectFactoryImpl.java:38)
at org.testng.internal.ClassHelper.createInstance1(ClassHelper.java:387)
at org.testng.internal.ClassHelper.createInstance(ClassHelper.java:299)
at org.testng.internal.ClassImpl.getDefaultInstance(ClassImpl.java:110)
at org.testng.internal.ClassImpl.getInstances(ClassImpl.java:186)
at org.testng.internal.TestNGClassFinder.<init>(TestNGClassFinder.java:120)
at org.testng.TestRunner.initMethods(TestRunner.java:409)
at org.testng.TestRunner.init(TestRunner.java:235)
at org.testng.TestRunner.init(TestRunner.java:205)
at org.testng.TestRunner.<init>(TestRunner.java:160)
at org.testng.remote.RemoteTestNG.newTestRunner(RemoteTestNG.java:141)
at org.testng.remote.RemoteTestNG$DelegatingTestRunnerFactory.newTestRunner(RemoteTestNG.java:271)
at org.testng.SuiteRunner$ProxyTestRunnerFactory.newTestRunner(SuiteRunner.java:577)
at org.testng.SuiteRunner.init(SuiteRunner.java:157)
at org.testng.SuiteRunner.<init>(SuiteRunner.java:111)
at org.testng.TestNG.createSuiteRunner(TestNG.java:1299)
at org.testng.TestNG.createSuiteRunners(TestNG.java:1286)
at org.testng.TestNG.runSuitesLocally(TestNG.java:1140)
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)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
at org.testng.internal.ObjectFactoryImpl.newInstance(ObjectFactoryImpl.java:29)
... 21 more
Caused by: java.lang.StackOverflowError
at unitTest.myTest.Global.<init>(Global.java:12)
at unitTest.myTest.BrowserInitializer.<init>(BrowserInitializer.java:6)
at unitTest.myTest.Global.<init>(Global.java:14)
but when i am initializing the driver instance in the constructor of the Global class i am able to run my test. what seems to be the problem? am i going wrong somewhere in the concepts of java?
但是当我在 Global 类的构造函数中初始化驱动程序实例时，我能够运行我的测试。似乎是什么问题？我在java概念中的某个地方出错了吗？
采纳答案by rocketboy
You have infinite recursion when calling Global's constructor. Your initialize()is perfectly fine.
调用 Global 的构造函数时，您有无限递归。你initialize()的完全没问题。
public Global()
{
BrowserInitializer obj=new BrowserInitializer();
obj.initialize();
}
BrowserInitializeris aGlobal.
BrowserInitializer是一个Global。
So Global's contructor calls BrowserInitializer's constructor (which calls super's i.e Global's constructor again)
SoGlobal的构造BrowserInitializer函数调用了的构造函数（它再次调用了superie Global的构造函数）
Use something like:
使用类似的东西：
public class BrowserInitializer extends Global
{
BrowserInitializer(){
super();
this.initialize();
}
public void initialize()
{
driver=new FirefoxDriver();
driver.manage().window().maximize();
wait=new WebDriverWait(driver, 5000);
}
}
//In test class
Global globalObj=new BrowserInitializer();
回答by Robbie Wareham
I woudl approach this in a different way, and use a @BeforeTes annotation;
我会以不同的方式处理这个问题，并使用@BeforeTes 注释；
Create a new webdriver class which extends Firefox driver;
创建一个新的 webdriver 类来扩展 Firefox 驱动程序；
public class MyFirefoxDriver extends FirefoxDriver {
private WebDriverWait wait;
private WebDriver driver;
public MyFirefoxDriver()
{
super();
this.manage().window().maximize();
wait = new WebDriverWait(this, 5000);
}
public WebDriverWait getWebDriverWait() {
return wait;
}
}
Your test would then look like this;
您的测试将如下所示；
public class TestNG1
{
private MyFirefoxDriver driver;
@BeforeTest
public void setUp() {
driver = new MyFirefoxDriver();
}
@Test
public void login()
{
driver.get("someURL");
driver.findElement(By.id("someid")).sendKeys("someusername");
driver.findElement(By.id("someid")).sendKeys("somepassword");
driver.findElement(By.id("someid")).submit();
//To access the wait;
WebDriverWait wait = driver.getWebDriverWait();
}
@AfterTest
public void tearDown() {
driver.quit();
}
}
I would be tempted to then further create a base test class;
然后我很想进一步创建一个基础测试类；
public abstract class TestNGBase
{
private MyFirefoxDriver driver;
public MyFirefoxDriver getDriver() {
return driver;
}
@BeforeTest
public void setUp() {
driver = new MyFirefoxDriver();
}
@AfterTest
public void tearDown() {
driver.quit();
}
}
In which case you test would then look like this;
在这种情况下，您的测试将如下所示；
public class TestNG1 extends TestNGBase
{
@Test
public void login()
{
getDriver().get("someURL");
getDriver().findElement(By.id("someid")).sendKeys("someusername");
getDriver().findElement(By.id("someid")).sendKeys("somepassword");
getDriver().findElement(By.id("someid")).submit();
//To access the wait;
WebDriverWait wait = getDriver().getWebDriverWait();
}
}
