android-studio - 无法获得gradle接受android studio 3中的java-client-6.0.0-BETA1.jar

Question

我是android studio的新手。我正在尝试使用appium的java-client-6.0.0-BETA1.jar来构建Android Studio Gradle。我正在实施鸦片。我相信android studio已安装正确。我已经下载了appium的推荐文件，selenium-server-standalone-3.8.1.jar，selenium-remote-driver.jar，selenium-java-3.8.1.zip和其他我认为需要的文件。 Appium服务器已安装并正在运行。一个android模拟器正在运行。
我收到此错误：

Caused by: com.android.builder.dexing.DexArchiveBuilderException: Failed to process C:\Repositories\ApkProjects\EndToEndAndroidTest\app\libs\java-client-6.0.0-BETA1.jar
    at com.android.build.gradle.internal.transforms.DexArchiveBuilderTransform.launchProcessing(DexArchiveBuilderTransform.java:550)
    at com.android.build.gradle.internal.transforms.DexArchiveBuilderTransform.lambda$convertToDexArchive$1(DexArchiveBuilderTransform.java:488)
    at java.util.concurrent.ForkJoinTask$AdaptedCallable.exec(ForkJoinTask.java:1424)
    at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289)
    at java.util.concurrent.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1056)
    at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1692)
    at java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:157)
Caused by: com.android.builder.dexing.DexArchiveBuilderException: Error while dexing io/appium/java_client/touch/TapOptions.class
The dependency contains Java 8 bytecode. Please enable desugaring by adding the following to build.gradle
android {
    compileOptions {
        sourceCompatibility 1.8
        targetCompatibility 1.8
    }

我尝试了推荐的修复程序-没什么区别。我已经更新了guava-23.3-android，它也给出了类似的错误。
gradle.build文件是：

    apply plugin: 'com.android.application'

android {
    compileSdkVersion 26
    defaultConfig {
        applicationId "com.nwri.endtoendandroidtest"
        minSdkVersion 18
        targetSdkVersion 26
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'com.android.support:appcompat-v7:26.1.0'
    implementation 'com.android.support.constraint:constraint-layout:1.0.2'
    implementation 'com.android.support:design:26.1.0'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.1'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.1'
//    compile 'com.google.guava:guava:23.3-android'
}

我已经在网上搜索过，找不到任何有此问题的人。如果有帮助，请看以下屏幕截图：
Android studio

Answer 1

在“项目结构”对话框中将Source Compatibility和Target Compatibility设置为1.8可以帮助我。

手动添加时

android {
    compileOptions {
        sourceCompatibility 1.8
        targetCompatibility 1.8
    }
}

没有帮助。