build.gradle

// Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript {
    repositories {

        google()
        maven{ url 'http://maven.aliyun.com/nexus/content/groups/public/'}
        jcenter()
        //maven { url 'https://dl.google.com/dl/android/maven2/'}
        mavenCentral() // add repository
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.4.1'
        classpath 'org.greenrobot:greendao-gradle-plugin:3.2.2' // add  GreenDao plugin
        classpath "io.realm:realm-gradle-plugin:2.2.1"
        // NOTE: Do not place your application dependencies here; they belong  in the individual module build.gradle files

    }
}

allprojects {
    repositories {

        google()
        maven{ url 'http://maven.aliyun.com/nexus/content/groups/public/'}
        maven { url 'https://jitpack.io' }
        jcenter()
        //maven { url 'https://dl.google.com/dl/android/maven2/'}


    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}