java.lang.NoSuchFieldError: INSTANCE exception is thrown by appium driver varriable

问题

I am trying to write this java class that opens an apk file in an android device and presses some buttons through appium,using the code below:

package new_appium_test;

import io.appium.java_client.android.AndroidDriver;
import io.appium.java_client.remote.MobileCapabilityType;

import java.io.File;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.concurrent.TimeUnit;

import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.remote.DesiredCapabilities;


public class new_appium_test {
    public MobileDriver driver;
    @Before
    public void setUp() throws MalformedURLException, InterruptedException, Exception {
    DesiredCapabilities capabilities = new DesiredCapabilities();
    capabilities.setCapability(MobileCapabilityType.PLATFORM_NAME,"Android");
    capabilities.setCapability(MobileCapabilityType.DEVICE_NAME, "GT-I9300"); //specify your cellphone name
    capabilities.setCapability(MobileCapabilityType.PLATFORM_VERSION,"4.3"); //specify the platform version
    capabilities.setCapability("platformName", "Android");
    capabilities.setCapability("appium-version", "1.2.4.1");
    capabilities.setCapability("appPackage","wizzo.mbc.net");
    capabilities.setCapability("appActivity","wizzo.mbc.net.activities.SplashActivity");
    driver = new AndroidDriver(new URL("http://127.0.0.1:4723/wd/hub"), capabilities);
    }

    driver.manage().timeouts().implicitlyWait(5, TimeUnit.SECONDS);
    }
    @Test
    public void chooseEnglish() throws Exception
    {
    driver.findElement(By.name("English")).click();
    }
    @After
    public void tearDown() throws Exception {
    driver.quit();
    }
}

although this failure trace appears:

java.lang.NoSuchFieldError: INSTANCE
    at org.apache.http.conn.ssl.SSLConnectionSocketFactory.<clinit>(SSLConnectionSocketFactory.java:144)
    at org.openqa.selenium.remote.internal.HttpClientFactory.getClientConnectionManager(HttpClientFactory.java:71)
    at org.openqa.selenium.remote.internal.HttpClientFactory.<init>(HttpClientFactory.java:57)
    at org.openqa.selenium.remote.internal.HttpClientFactory.<init>(HttpClientFactory.java:60)
    at org.openqa.selenium.remote.internal.ApacheHttpClient$Factory.getDefaultHttpClientFactory(ApacheHttpClient.java:251)
    at org.openqa.selenium.remote.internal.ApacheHttpClient$Factory.<init>(ApacheHttpClient.java:228)
    at org.openqa.selenium.remote.HttpCommandExecutor.getDefaultClientFactory(HttpCommandExecutor.java:89)
    at org.openqa.selenium.remote.HttpCommandExecutor.<init>(HttpCommandExecutor.java:63)
    at org.openqa.selenium.remote.HttpCommandExecutor.<init>(HttpCommandExecutor.java:58)
    at org.openqa.selenium.remote.RemoteWebDriver.<init>(RemoteWebDriver.java:155)
    at io.appium.java_client.DefaultGenericMobileDriver.<init>(DefaultGenericMobileDriver.java:22)
    at io.appium.java_client.AppiumDriver.<init>(AppiumDriver.java:202)
    at io.appium.java_client.android.AndroidDriver.<init>(AndroidDriver.java:50)
    at new_appium_test.new_appium_test.setUp(new_appium_test.java:34)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.junit.internal.runners.BeforeAndAfterRunner.invokeMethod(BeforeAndAfterRunner.java:74)
    at org.junit.internal.runners.BeforeAndAfterRunner.runBefores(BeforeAndAfterRunner.java:50)
    at org.junit.internal.runners.BeforeAndAfterRunner.runProtected(BeforeAndAfterRunner.java:33)
    at org.junit.internal.runners.TestMethodRunner.runMethod(TestMethodRunner.java:75)
    at org.junit.internal.runners.TestMethodRunner.run(TestMethodRunner.java:45)
    at org.junit.internal.runners.TestClassMethodsRunner.invokeTestMethod(TestClassMethodsRunner.java:71)
    at org.junit.internal.runners.TestClassMethodsRunner.run(TestClassMethodsRunner.java:35)
    at org.junit.internal.runners.TestClassRunner$1.runUnprotected(TestClassRunner.java:42)
    at org.junit.internal.runners.BeforeAndAfterRunner.runProtected(BeforeAndAfterRunner.java:34)
    at org.junit.internal.runners.TestClassRunner.run(TestClassRunner.java:52)
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)

the problem is located on the command driver = new AndroidDriver(new URL("http://127.0.0.1:4723/wd/hub"), capabilities);. Can anyone please tell me why this is happening?

回答1:

NoSuchfield exception is thrown if an application tries to access or modify a specified field of an object, and that object no longer has that field. If this error is happening at the Android driver instantiation, then it could be that some of capabilites you have may not be right. There is no such capability as appium-version - Link. Also device_name is ignored for Android. Try out below capabilities

 DesiredCapabilities capabilities = new DesiredCapabilities();
    capabilities.setCapability(MobileCapabilityType.AUTOMATION_NAME,
     "Selendroid");
    capabilities.setCapability(MobileCapabilityType.PLATFORM_NAME, "Android");
    capabilities.setCapability(MobileCapabilityType.PLATFORM_VERSION, "4.3");
    capabilities.setCapability(MobileCapabilityType.APP_PACKAGE: "wizzo.mbc.net");
    capabilities.setCapability(MobileCapabilityType.APP_ACTIVITY: "wizzo.mbc.net.activities.SplashActivity");

来源：https://stackoverflow.com/questions/32120188/java-lang-nosuchfielderror-instance-exception-is-thrown-by-appium-driver-varria