线程“main”中的异常 org.openqa.selenium.StaleElementReferenceException：在缓存中找不到元素

Question

有人可以帮忙吗？我有错误

"Exception in thread “main” org.openqa.selenium.StaleElementReferenceException: Element not found in the cache"

为什么显示这个错误？我需要将鼠标悬停在每个类别菜单上，而不是单击子菜单中的每个文本。

public class santander {
  private static WebDriver driver = null;     
  public static JavascriptExecutor js = (JavascriptExecutor) driver;
  public static void main(String[] args) throws FileNotFoundException, InterruptedException, IOException {
        // TODO Auto-generated method stub
        driver = new FirefoxDriver();
        driver.manage().timeouts().implicitlyWait(10, TimeUnit.SECONDS);
        driver.get("http://www.santander.co.uk/uk/index");




    driver.manage().window().maximize();
    driver.get("http://www.santander.co.uk/uk/index");

    JavascriptExecutor js = (JavascriptExecutor) driver;

    WebDriverWait wait = new WebDriverWait(driver, 10);  

    String submenutxtlinks = "submenu.txt";

    List<String> submenu = new ArrayList<String>();
    BufferedReader reader = new BufferedReader(new FileReader(submenutxtlinks));
    String line;
      while ((line = reader.readLine()) != null) {
          submenu.add(line);
      }
      reader.close();



      Actions action = new Actions(driver);
     /* 
     WebElement menu = driver.findElement(By.linkText("Current Accounts"));
     action.moveToElement(menu).perform();
     WebElement submenu = driver.findElement(By.linkText("See all current accounts"));
     action.moveToElement(submenu);
     action.click();
     action.perform();
     */   



       // String title = driver.getTitle();

       // wait.until(ExpectedConditions.titleIs(title));
      //  driver.navigate().back();

    //Loop to read all lines one by one from file and print It.
     // while((menu = BR.readLine())!= null && !menu.isEmpty()){



         // driver.manage().timeouts().implicitlyWait(10, TimeUnit.SECONDS);

        //  Action hovering = action.moveToElement(a).build();
        //  hovering.perform();

          //action.moveToElement(a).perform();
          //action.clickAndHold(a).perform();
      WebElement a = driver.findElement(By.cssSelector("#nav > div.navMain > div.nav_menu > nav > ul > li:nth-child(1) > a"));
      Action hovering = action.moveToElement(a).build();
      //Thread.sleep(2000);

    for (int i=0;i<=submenu.size()-1;i++ ) {

        //String b = submenu.get(i);

       // System.out.println(b); 

        //WebElement b = driver.findElement(By.xpath(submenu.get(i)));
        try{
            //Your code which causes exception




        hovering.perform();


        //action.moveToElement(b).click(b).build().perform();
        Thread.sleep(1000); 

        clickAnElementByLinkText(submenu.get(i));
        //b.click();
        Thread.sleep(1000);
          /*
        wait.until(ExpectedConditions.visibilityOf(b));
        action.moveToElement(b);
        action.click();
        action.perform();
        */
  //  wait.until(ExpectedConditions.titleIs(title));

      driver.navigate().back();

        //driver.manage().timeouts().implicitlyWait(10, TimeUnit.SECONDS);
        Thread.sleep(2000);
   // driver.get("http://www.santander.co.uk/uk/index");
        //driver.navigate();
        Thread.sleep(2000);
  //  driver.manage().timeouts().implicitlyWait(10, TimeUnit.SECONDS);
        }
        catch(org.openqa.selenium.StaleElementReferenceException e){
            //Repeat the code in try
            }


}

 // } 

    driver.close();
}



public static void clickAnElementByLinkText(String linkText) {

  WebDriverWait wait = new WebDriverWait(driver, 10);
  wait.until(ExpectedConditions.presenceOfElementLocated(By.xpath(linkText)));
  driver.findElement(By.xpath(linkText)).click();
  }
}

Answer 1

您正在尝试访问一个不存在的元素。

代码收集了页面上的元素，
然后代码点击了一个改变源的元素
然后它尝试访问他在之前收集的一个对象，但它不再存在（你看到的是一个新的） .

可以将查找元素的过程进入循环，每次迭代循环改变'i'元素（如果每次迭代都必须点击元素）。

Answer 2

不要在同一上下文中混用 ImplicitWait ExplicitWait 和 Thread.Sleep。
Learn when and where those should be used.

hoverElement 将无法工作，因为驱动程序导航到不同的页面并且元素不再存在您已在 forLoop 中再次找到它

为了测试，我对子菜单列表进行了硬编码

此代码将执行您要求的操作

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.concurrent.TimeUnit;
import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.firefox.FirefoxDriver;
import org.openqa.selenium.interactions.Actions;
import org.openqa.selenium.support.ui.ExpectedConditions;
import org.openqa.selenium.support.ui.WebDriverWait;

public class ListTest {

static WebDriver driver;

public static void main(String[] args) {
    List<String> submenu = new ArrayList<>(Arrays.asList(new String[]{"See all current accounts", "1|2|3 Current Account", "Everyday Current Account", "Basic Current Account", "Choice Current Account"}));
    driver = new FirefoxDriver();
    driver.manage().timeouts().implicitlyWait(10, TimeUnit.SECONDS);
    driver.manage().window().maximize();
    driver.get("http://www.santander.co.uk/uk/index");
    for (String sMenu : submenu) {
        WebElement a = driver.findElement(By.cssSelector("#nav > div.navMain > div.nav_menu > nav > ul > li:nth-child(1) > a"));
        new Actions(driver).moveToElement(a).build().perform();
        clickAnElementByLinkText("//li[@role='listitem']/a[normalize-space(text())='" + sMenu + "']");
        driver.navigate().back();
    }
    driver.quit();
}

public static void clickAnElementByLinkText(String linkText) {
    WebDriverWait wait = new WebDriverWait(driver, 10);
    wait.until(ExpectedConditions.presenceOfElementLocated(By.xpath(linkText))).click();
}
}

线程“main”中的异常 org.openqa.selenium.StaleElementReferenceException：在缓存中找不到元素

Exception in thread “main” org.openqa.selenium.StaleElementReferenceException: Element not found in the cache

java

selenium

multithreading

webdriver