使用AS生成包含ASSETS的JAR包

task makeJar(type: Jar){
    from zipTree(file('build/intermediates/bundles/release/classes.jar'))
    from fileTree(dir:'src/main',includes:['assets/**'])
    baseName = "sdk_${android.defaultConfig.versionName}_un"
    destinationDir = file('build')
}

makeJar.dependsOn(build)