Improvement at interface in WebElement and SearchContext

[leocarmona]

I was wondering if is possible to change the return the generic type for this method below of the interfaces SearchContext and WebElement:

List< WebElement> findElements(By by)

to

List<? extends WebElement> findElements(By by);

import java.util.Arrays;
import java.util.List;

import org.openqa.selenium.By;
import org.openqa.selenium.StaleElementReferenceException;
import org.openqa.selenium.Dimension;
import org.openqa.selenium.OutputType;
import org.openqa.selenium.Point;
import org.openqa.selenium.Rectangle;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebDriverException;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.internal.WrapsDriver;
import org.openqa.selenium.internal.WrapsElement;

public class NewWebElement implements WebElement, WrapsDriver, WrapsElement {

	private WebElement wrappedElement;

	public NewWebElement(WebElement wrappedElement) {
		this.wrappedElement = wrappedElement;
	}
	
	public boolean isPresent() {
		try {
			this.getWrappedElement().isEnabled();
			
			return true;
		} catch (StaleElementReferenceException e) {
			return false;
		}
	}

	/**
	 * I want to created a class to extends the functionality of WebElement	
	 * Today because of the interface the code List<NewWebElement> will not compile although the NewWebElement implements WebElement.
	 * If the return chenged to List<? extends WebElement> will be possible create new custom functionalities. 
	 */
	@Override
	public List<NewWebElement> findElements(By by) {
		List<WebElement> webElements = this.getWrappedElement().findElements(by);
		NewWebElement[] newWebElements = new NewWebElement[webElements.size()];
		
		for (int i = 0; i < newWebElements.length; i++)
			newWebElements[i] = new NewWebElement(webElements.get(i));
		
		return Arrays.asList(newWebElements);
	}
	
	// Add unimplemented methods

}

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.firefox.FirefoxDriver;

public class Sample {

	public static void main(String[] args) {
		WebDriver driver = new FirefoxDriver();
		driver.get("https://www.google.com");
		
		WebElement body = driver.findElement(By.tagName("body"));
		By search = By.id("lst-ib");
		
		// I will be able to find within an element and access my custom methods
		
		new newWebElement(body).findElements(search).get(0).isPresent();
	}
	
}

[lukeis]

WebElement is an interface, so you have to honor the contract of that interface. You could do so by doing the following:

@Override
public List<WebElement> findElements(By by) {
    List<WebElement> webElements = this.getWrappedElement().findElements(by);
    List<WebElement> newWebElements = new ArrayList<>();

    for (WebElement webElement : webElements) {
        newWebElements.add(new NewWebElement(webElement));
    }
    return newWebElements;
}

Your code later would then look like:
((newWebElement)new newWebElement(body).findElements(search).get(0)).isPresent();

If you want to avoid the casting, then you should provide an alternative method name and have it return your class, like public List<newWebElement> findNewElements(By by)

changing the interfaces is not someone that can be done easily.. this Pull request would need to be revisited #863

That pull request stalled it seems because they worked around the issue by wrapping all the classes instead (appium/java-client@3183ebe). Which is a recommend approach, rather than modifying the existing interfaces.

Closing this is as 'won't fix' (for now)