不兼容的类型：java.lang.Object无法转换为org.openqa.selenium.WebElement

Question

package Selenium.Locators;
import java.util.List;
import java.net.URL;
import java.util.ArrayList;
import org.openqa.selenium.By;
import org.openqa.selenium.JavascriptExecutor;
import org.openqa.selenium.Keys;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.SearchContext;
import org.openqa.selenium.TakesScreenshot;
import org.openqa.selenium.firefox.FirefoxDriver;
import sun.net.www.protocol.http.HttpURLConnection;
public class program { 
// to get all the links in a website which has anchor tag and img tag
public static List findAllLinks(WebDriver driver)
{
    List elementList = new ArrayList();
    elementList = driver.findElements(By.tagName("a"));
    elementList.addAll(driver.findElements(By.tagName("img")));// to get the anchor tag and img tag values
    List finalList = new ArrayList(); 
    for (WebElement element : elementList)//it shows error in this line
    {
        if(element.getAttribute("href") != null)
        {
            finalList.add(element);
        }
    }
    return finalList;
}
// to find all the broken links in a  website
public static String isLinkBroken(URL url) throws Exception
{
    url = new URL("https://www.yahoo.com/");// to find the broken links 
    String response = ""
    HttpURLConnection connection = (HttpURLConnection) url.openConnection();
    try
    {
        connection.connect();
        response = connection.getResponseMessage();
        connection.disconnect();
        return response;
    }
    catch(Exception exp)
    {
        return exp.getMessage();
    }
}
public static void main(String[] args) throws Exception {
    // TODO Auto-generated method stub
    System.setProperty("webdriver.gecko.driver", "G:\\AllLinks\\src\\test\\java\\Selenium\\Locators\\geckodriver.exe");
    FirefoxDriver ff = new FirefoxDriver();
    ff.get("https://www.yahoo.com/");
    List allImages = findAllLinks(ff);
    System.out.println("Total number of elements found " + allImages.size());
    for (WebElement element : allImages)// It shows the error in this line
        try
        {
            System.out.println("URL: " + element.getAttribute("href")+ " returned " + isLinkBroken(new URL(element.getAttribute("href"))));
            //System.out.println("URL: " + element.getAttribute("outerhtml")+ " returned " + isLinkBroken(new URL(element.getAttribute("href"))));
        }
        catch(Exception exp)
        {
            System.out.println("At " + element.getAttribute("innerHTML") + " Exception occured -> " + exp.getMessage());
        }
    }
}

If i run the code i get the following error message Error:(69, 35) java: incompatible types: java.lang.Object cannot be converted to org.openqa.selenium.WebElement This code is used for getting all the links in a website so that we can test it manually for finding all the element.

Answer 1

如@Shekhar Swami所述，您应该定义网络元素列表，如下所示

List<WebElement> elementList = driver.findElements(By.tagName("a"));

Answer 2

In following line of your code:

List elementList = new ArrayList();

List is Generic interface in java you need to provide a type while initializing it. If you don't provide one, it will take java.lang.Object as its type by default.

for (WebElement element : elementList)

Here you are extracting each of the element on that list which have type Object, and your element variable is of type WebElement .

For making your code work. do the following changes in that line

List<WebElement> elementList = new ArrayList<WebElement>();

Reference for Generic Types in java : Click here

Answer 3

following is the error

Error:(69, 35) java: incompatible types: java.lang.Object cannot be converted to org.openqa.selenium.WebElement

it means, Your List is incompatible with WebElement , so you have to define and instantiate List as WebElement type like this

List<WebElement> elementList = driver.findElements(By.tagName("a"));

Try this and let me know

just for example I have used like this:

List<WebElement> TotalLinks = driver.findElements(By.tagName("a"));
System.out.println("Links count is: "+TotalLinks .size());
for(WebElement link : TotalLinks )
System.out.println(link.getText());