安卓Gradle repository庫搜索順序

buildscript repositories搜索順序

buildscript { repositories { jcenter() google() }}

1. BintrayJCenter
2. maven
3. Google

參考：gradle assembleDebug --debug日誌

[org.gradle.api.internal.artifacts.ivyservice.ivyresolve.RepositoryChainComponentMetaDataResolver] Attempting to resolve component for com.android.tools:annotations:26.0.1 using repositories [BintrayJCenter, maven, Google]

project repositories搜索順序

allprojects { repositories { jcenter() google() }}

1. ${ANDROID_HOME}/extras/m2repository，目前用於存放constraint-layout和constraint-layout-resolver
2. ${ANDROID_HOME}/extras/google/m2repository
3. ${ANDROID_HOME}/extras/android/m2repository，目前用於存放databinding和android-support
4. BintrayJCenter
5. maven
6. Google（如果有配置）
7. flatDir（如果有配置）

參考：gradle assembleDebug --debug日誌

[org.gradle.api.internal.artifacts.ivyservice.ivyresolve.RepositoryChainComponentMetaDataResolver] Attempting to resolve component for com.squareup.leakcanary:leakcanary-android:1.5.4 using repositories [${ANDROID_HOME}/extras/m2repository, ${ANDROID_HOME}/extras/google/m2repository, ${ANDROID_HOME}/extras/android/m2repository, BintrayJCenter, maven, Google, flatDir]

總結

在Gradle 4.0中，BintrayJCenter、maven、Google、flatDir的順序是固定的。是否使用Google和flatDir取決於有無配置。