Exception in thread "main" java.lang.NoClassDefFoundError when running Appium using Java

Question

Trying to automate native app on android device using Appium (Java) and faced this error:

Exception in thread "main" java.lang.NoClassDefFoundError: org/openqa/selenium/remote/internal/JsonToWebElementConverter at wibu.main(wibu.java:21)

Caused by: java.lang.ClassNotFoundException: org.openqa.selenium.remote.internal.JsonToWebElementConverter at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:641) at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:188) at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:520) ... 1 more

Here's my code:

import io.appium.java_client.MobileElement;
import io.appium.java_client.android.AndroidDriver;
import io.appium.java_client.android.AndroidElement;
import io.appium.java_client.remote.MobileCapabilityType;
import org.openqa.selenium.remote.DesiredCapabilities;

import java.net.MalformedURLException;
import java.net.URL;

public class wibu {

    public static void main(String[] args) throws MalformedURLException {

        DesiredCapabilities dc = new DesiredCapabilities();

        dc.setCapability(MobileCapabilityType.DEVICE_NAME, "emulator-5554");
        dc.setCapability("platformName", "android");
        dc.setCapability("appPackage", "com.facebook.katana");
        dc.setCapability("appActivity", "com.facebook.katana.LoginActivity");

        AndroidDriver<AndroidElement> ad = new AndroidDriver<AndroidElement>(new URL("http://127.0.0.1:4723/wd/hub"),dc);

        String facebook_username = "username";
        String facebook_password = "password";

        MobileElement el1 = (MobileElement) ad.findElementByAccessibilityId("Username");
        el1.sendKeys(facebook_username);
        MobileElement el2 = (MobileElement) ad.findElementByAccessibilityId("Password");
        el2.sendKeys(facebook_password);
        MobileElement el3 = (MobileElement) ad.findElementByAccessibilityId("Log In");
        el3.click();
        MobileElement el4 = (MobileElement) ad.findElementByXPath("/hierarchy/android.widget.FrameLayout/android.widget.LinearLayout/android.widget.FrameLayout/android.widget.FrameLayout/android.widget.LinearLayout/android.widget.FrameLayout/android.widget.LinearLayout/android.widget.LinearLayout/android.widget.Button[1]");
        el4.click();
        MobileElement el5 = (MobileElement) ad.findElementById("com.google.android.gms:id/credential_save_reject");
        el5.click();

    }
}

Answer 1

So eventually,

the original issue was that java-client 7.6.0 is not compatible with Selenium 4.

In order to use Selenium 4, appium version should be 8+.

The latest appium-java client version is 8.0.0-beta2

https://mvnrepository.com/artifact/io.appium/java-client/8.0.0-beta2

Migration from Appium 7 to 8

The list of breaking changes listed in this guide:

https://github.com/appium/java-client/blob/master/docs/v7-to-v8-migration-guide.md

• AndroidDriver<AndroidElement> should be AndroidDriver
• MobileElement should be WebElement
• findElementByAccessibilityId should be findElement(AppiumBy.accessibilityId("...")), etc.

And for double-check, the recent API docs available here:

https://javadoc.io/doc/io.appium/java-client/latest/index.html