4.0.0 androidx.collection collection 1.0.0 Android Support Library collections Standalone efficient collections. http://developer.android.com/tools/extras/support-library.html 2018 The Apache Software License, Version 2.0 http://www.apache.org/licenses/LICENSE-2.0.txt repo The Android Open Source Project scm:git:https://android.googlesource.com/platform/frameworks/support http://source.android.com junit junit 4.12 test androidx.annotation annotation 1.0.0 compile