基于Android 7.0的源码分析
一.概述
前面介绍过AMS相关的一些数据结构，每个数据结构有大量的成员变量，为了查询当前手机运行时状态的 变化值，可以通过dumpsys activity命令来完成，该方法最终是调用AMS.dump()方法。
dumpsys命令用法简要介绍过dumpsys命令 的基本用法，以及系统服务列表信息，那么本文重点介绍AMS。 根据dumpsys activity传递不同的参数， 对于AMS.dump便会输出相应的对象信息。 具体可以跟哪些参数.
1.1 命令格式
dumpsys activity [options] [WHAT]
其中options为可选项，以-开头， 主要有以下几类：
| options | 含义 |
|---|---|
| -a | 包括所有可用Server状态 |
| -c | 包括Client状态，即App端情况 |
| -p PACKAGE | 限定输出指定包名 |
1.2 WHAT参数
列举常见的WHAT参数：
| 序号 | WHAT | 解释 | 对应源码 |
|---|---|---|---|
| 1 | a[ctivities] | activity状态 | dumpActivitiesLocked() |
| 2 | b[roadcasts] [PACKAGE_NAME] | broadcast状态 | dumpBroadcastsLocked() |
| 3 | s[ervices] [COMP_SPEC …] | service状态 | newServiceDumperLocked().dumpLocked |
| 4 | prov[iders] [COMP_SPEC …] | content provider状态 | dumpProvidersLocked() |
| 5 | p[rocesses] [PACKAGE_NAME] | 进程状态 | dumpProcessesLocked() |
| 6 | o[om] | 内存管理 | dumpOomLocked() |
| 7 | i[ntents] [PACKAGE_NAME] | pending intent状态 | dumpPendingIntentsLocked() |
| 8 | r[ecents] | 最近activity | dumpRecentsLocked() |
| 9 | perm[issions] | URI授权情况 | dumpPermissionsLocked() |
| 10 | all | 所有activities信息 | dumpActivity() |
| 11 | top | 顶部activity信息 | dumpActivity() |
| 12 | package | package相关信息 | dump() |
其中PACKAGE_NAME是指可跟包名，COMP_SPEC是指可跟具体组件信息，中括号是指缩写字母；
二. dumpsys activity
前面介绍dumpsys activity根据后面跟着的不同参数则输出相应的内容，当不跟任何参数，
dumpsys activity等价于依次输出下面8条命令：
dumpsys activity intents
dumpsys activity broadcasts //广播
dumpsys activity providers //provider
dumpsys activity permissions
dumpsys activity services //服务
dumpsys activity recents
dumpsys activity activities //activity
dumpsys activity processes
依次简要说明这8条命令：
2.1 intents
//标志性开头，dumpPendingIntentsLocked
ACTIVITY MANAGER PENDING INTENTS (dumpsys activity intents)
输出对象：
- PendingIntentRecord
2.2 broadcasts
//标志性开头，dumpBroadcastsLocked
ACTIVITY MANAGER BROADCAST STATE (dumpsys activity broadcasts)
Registered Receivers：
Receiver Resolver Table：
Historical broadcasts [foreground]:
Historical broadcasts summary [foreground]:
Historical broadcasts [background]:
Historical broadcasts summary [background]:
Sticky broadcasts
mHandler
主要输出的对象：
- ReceiverList, BroadcastFilter,
- IntentResolver,
- BroadcastQueue, BroadcastRecord
- Handler, Looper
2.3 provider
//标志性开头，dumpProvidersLocked
ACTIVITY MANAGER CONTENT PROVIDERS (dumpsys activity providers)
Published single-user content providers (by class):
Published user [n] content providers (by class):
Single-user authority to provider mappings:
User [n] authority to provider mappings:
主要输出的对象：
- ProviderMap
- ContentProviderRecord， ContentProviderConnection
2.4 permissions
//标志性开头，dumpPermissionsLocked
ACTIVITY MANAGER URI PERMISSIONS (dumpsys activity permissions)
主要输出的对象：
- UriPermission
2.5 Service
//标志性开头，newServiceDumperLocked().dumpLocked
ACTIVITY MANAGER SERVICES (dumpsys activity services)
主要输出的对象：
- ActiveServices,
- ServiceRecord, ConnectionRecord,ProcessRecord
2.6 recents
//标志性开头，dumpRecentsLocked
ACTIVITY MANAGER RECENT TASKS (dumpsys activity recents)
主要输出的对象：
- TaskRecord
2.7 activities
//标志性开头，dumpActivitiesLocked
ACTIVITY MANAGER ACTIVITIES (dumpsys activity activities)
Display #0 (activities from top to bottom):
Stack #0:
Task id #[n]
* Hist #[m]:
Stack #1:
主要输出的对象：
- ActivityStackSupervisor, ActivityStack,
- TaskRecord, ActivityRecord
- ActivityThread, Activity
- ViewRootImpl
- Looper, MessageQueue
输出格式样例：
//{Hashcode #TaskId Affinity UserId 该task的Activity个数}；
TaskRecord{e6d7a8e #156 A=com.gityuan.demo U=0 sz=1}
userId=0 effectiveUid=1000 mCallingUid=1000 mCallingPackage=android
realActivity=com.gityuan.demo/.Blog
//ProcessRecord{Hashcode pid:进程名/uid}
ProcessRecord{7c8a2af 12265:com.gityuan.demo/1000}
2.8 processes
//标志性开头，dumpProcessesLocked
ACTIVITY MANAGER RUNNING PROCESSES (dumpsys activity processes)
All known processes:
Isolated process list (sorted by uid):
UID states:
UID validation:
Process LRU list (sorted by oom_adj, 60 total, non-act at 2, non-svc at 2):
PID mappings:
Foreground Processes:
主要输出的对象：
- AMS各种进程对象
- ProcessRecord, UidRecord
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