初始化时 Selenium WebDriver NoElementException

Question

I have next code:

package pageobjects;

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.safari.SafariDriver;

public class MainPage {

    WebDriver driver = new SafariDriver();

    private String baseURL = "https://www.amazon.com";

    private WebElement searchLine = driver.findElement(By.cssSelector("#twotabsearchtextbox"));
    private WebElement searchButton = driver.findElement(By.cssSelector("input.nav-input"));

    public MainPage(){
        driver.get(baseURL);
    }

    public void searchItem(String query){
        searchLine.clear();
        searchLine.sendKeys(query);
        searchButton.click();
    }
}

And test:

import org.testng.annotations.Test;
import pageobjects.MainPage;

public class FirstSimpleTest {

    @Test
    public void verifySearchWork(){
        MainPage mainPage = new MainPage();
        mainPage.searchItem("Nike Air Max");
    }
}

Before browser runs I have next exception:

org.openqa.selenium.NoSuchElementException: 
For documentation on this error, please visit: http://seleniumhq.org/exceptions/no_such_element.html
Build info: version: '3.14.0', revision: 'aacccce0', time: '2018-08-02T20:19:58.91Z'
System info: host: 'Macbook.connectify', ip: 'fe80:0:0:0:1029:e2f6:81bd:b9e1%en0', os.name: 'Mac OS X', os.arch: 'x86_64', os.version: '10.14.2', java.version: '11'
Driver info: org.openqa.selenium.safari.SafariDriver
Capabilities {acceptInsecureCerts: false, browserName: Safari, browserVersion: 12.0.2, javascriptEnabled: true, platform: MAC, platformName: MAC, setWindowRect: true}
Session ID: 19412DA2-A6E4-40D5-89BE-1CE9310B8697
*** Element info: {Using=css selector, value=#twotabsearchtextbox}
at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:490)
at org.openqa.selenium.remote.http.W3CHttpResponseCodec.createException(W3CHttpResponseCodec.java:187)
at org.openqa.selenium.remote.http.W3CHttpResponseCodec.decode(W3CHttpResponseCodec.java:122)
at org.openqa.selenium.remote.http.W3CHttpResponseCodec.decode(W3CHttpResponseCodec.java:49)
at org.openqa.selenium.remote.HttpCommandExecutor.execute(HttpCommandExecutor.java:158)
at org.openqa.selenium.remote.service.DriverCommandExecutor.execute(DriverCommandExecutor.java:83)
at org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:548)
at org.openqa.selenium.remote.RemoteWebDriver.findElement(RemoteWebDriver.java:322)
at org.openqa.selenium.remote.RemoteWebDriver.findElementByCssSelector(RemoteWebDriver.java:416)
at org.openqa.selenium.By$ByCssSelector.findElement(By.java:431)
at org.openqa.selenium.remote.RemoteWebDriver.findElement(RemoteWebDriver.java:314)
at pageobjects.MainPage.<init>(MainPage.java:14)
at FirstSimpleTest.verifySearchWork(FirstSimpleTest.java:8)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:566)
at org.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:124)
at org.testng.internal.Invoker.invokeMethod(Invoker.java:583)
at org.testng.internal.Invoker.invokeTestMethod(Invoker.java:719)
at org.testng.internal.Invoker.invokeTestMethods(Invoker.java:989)
at org.testng.internal.TestMethodWorker.invokeTestMethods(TestMethodWorker.java:125)
at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:109)
at org.testng.TestRunner.privateRun(TestRunner.java:648)
at org.testng.TestRunner.run(TestRunner.java:505)
at org.testng.SuiteRunner.runTest(SuiteRunner.java:455)
at org.testng.SuiteRunner.runSequentially(SuiteRunner.java:450)
at org.testng.SuiteRunner.privateRun(SuiteRunner.java:415)
at org.testng.SuiteRunner.run(SuiteRunner.java:364)
at org.testng.SuiteRunnerWorker.runSuite(SuiteRunnerWorker.java:52)
at org.testng.SuiteRunnerWorker.run(SuiteRunnerWorker.java:84)
at org.testng.TestNG.runSuitesSequentially(TestNG.java:1208)
at org.testng.TestNG.runSuitesLocally(TestNG.java:1137)
at org.testng.TestNG.runSuites(TestNG.java:1049)
at org.testng.TestNG.run(TestNG.java:1017)
at org.testng.IDEARemoteTestNG.run(IDEARemoteTestNG.java:72)
at org.testng.RemoteTestNGStarter.main(RemoteTestNGStarter.java:123)

How can I fix it?

Answer 1

before using driver do get an WebElement , you should get a reference by www-address
so use driver to get WebElement after invoke get(baseUrl)

private WebElement searchLine;
public MainPage(){
    driver.get(baseURL);
    searchLine = driver.findElement(By.cssSelector("#twotabsearchtextbox"));
}