1. ActivityManagerService（AMS）:
處理來自 ActivityManager的調(diào)用（App 端的調(diào)用）颊乘，
然后轉(zhuǎn)發(fā)給 ATMS處理
frameworks/base/services/core/java/com/android/server/am/ActivityManagerService.java
2. ActivityTaskManagerService（ATMS）:
處理來自AMS 的請求鸠天， 又會轉(zhuǎn)發(fā)給 ASC/ 或者AS 處理
frameworks/base/services/core/java/com/android/server/wm/ActivityTaskManagerService.java
3. ActivityStarter(AS)
真正執(zhí)行啟動Activity
frameworks/base/services/core/java/com/android/server/wm/ActivityStarter.java
4. ActivityStartController(ASC)
創(chuàng)建并持有 AS 對象.
并做一些例外處理再交給 AS 最終啟動.
frameworks/base/services/core/java/com/android/server/wm/ActivityStartController.java
