できる！Android Framework Code Reading

Ͱ͖Δʂ
 
Android Framework
 
Code Reading
DroidKaigi 2021 Day 3

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• Shinobu Okano

• @operandoOS / shinobu.dart

• 10X, Inc. / Software Engineer

• Flutter / Dart / Android / Automation
ࣗݾ঺հ

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10X, Inc. - Stailer
https://stailer.jp/

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We are waiting for YOU!
https://jobs.10x.co.jp/

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͜ͷηογϣϯͷΰʔϧ
• Android Frameworkͷίʔυ͕ͳΜͱͳ͘ಡΊΔΑ͏ʹͳΔ

• πʔϧΛར༻ͯ͠ಡΈ͍ͨίʔυΛݟ͚ͭΒΕΔΑ͏ʹͳΔ

• Android Frameworkͷίʔυ͕ಡΈͨ͘ͳΔʂ

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Android Framework
 
ͬͯͳʹʁ

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Android software stack
• ͬ͘͟ΓݴͬͯAndroid OSΛߏ੒͍ͯ͠Δ΋ͷ

• ͍͔ͭ͘ͷLayerͰ෼͔Ε͍ͯΔ

• Android system architectureͱදݱ͞ΕΔ͜ͱ΋͋Δ

• ͱʹ͔͘޿͍ɾͰ͔͍ɾਂ͍ɾ΍͹͍

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https://source.android.com/index.html https://source.android.com/setup/intro

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• શLayerͷιʔείʔυ͕΄΅OSSͱͯ͠ެ։͞Ε͍ͯΔͷͰಡΊΔ

• Kotlin/JavaͰΞϓϦ։ൃ͍ͯ͠Δਓ͕ؾܰʹಡΊΔͷ͸ Android
Framework Layer

• Android Framework Layer͸͓͓͔ͨJavaͰॻ͔Ε͍ͯΔ

• ͦΕΑΓԼͷLayer͸C/C++ɺRustͳͲͰॻ͔Ε͍ͯΔ

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ຊࢿྉʹ͓͚ΔAndroid Framework
• Android Framework = Android software stack ͱ͍͏
 
Ґஔ͚ͮͰॻ͍͍ͯ·͢

• ͨͩ͠ຊࢿྉͰ঺հ͢Δ͜ͱ͸্ҐϨΠϠʔ޲͚ͷ
 
Code ReadingΛϝΠϯλʔήοτͱ͍ͯ͠·͢

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Android FrameworkͷίʔυΛಡΉཧ༝
• ಡΉ͜ͱͰ಺෦ͷ࢓૊ΈΛཧղ͠ɺΞϓϦ։ൃ౳ʹ໾ཱͯΔ

• ͳΜͱͳ͘಺෦ͷ࢓૊Έ஌Γ͍ͨͳʔͱ͍͏ڵຯ͕༙͍ͯ
 
͠·͏͔Β

• ָ͍͔͠Β☺

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Android Framework
 
Code ReadingΛ͢Δ্Ͱ
 
ศརͳαΠτɾπʔϧͷ঺հ

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Android Code Search
“Code Search with Cross References for the
Android Open Source Project”
https://android-developers.googleblog.com/2019/12/code-
search-with-cross-references-for-aosp.html

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Android Code Search
https://cs.android.com/

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Android Code Search(ACS)
• ϒϥ΢β্ͰAndroid FrameworkͷίʔυΛݕࡧɾӾཡ
 
Ͱ͖ΔαΠτ

• ίʔυྔ͕๲େͳAndroid FrameworkͷίʔυΛಡΉ্Ͱ
ඞਢπʔϧ

• Google͕ӡӦΛ͍ͯ͠Δ

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Android Code Searchͷ͍͢͝ͱ͜Ζ
• ݕࡧͷϑΟϧλʔ͕๛෋

• ߦ਺͕ଟ͍ίʔυͰ΋αΫαΫදࣔ͞ΕΔ

• ϒϥϯνͷ੾Γସ͕͑Ͱ͖Δ

• ૬ޓࢀরͷϦϯΫ͕షΒΕ͍ͯΔ

• ϝιουͷ֊૚ݺͼग़͠ɺࢀর͕Θ͔Δ

• Ξ΢τϥΠϯΊͪΌศརʂ

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ݕࡧͷϑΟϧλʔ͕๛෋
• ໨తͷίʔυΛ୳ͨ͢Ίʹ໾ཱͭϑΟϧλʔ͕͍ͬͺ͍

• ݕࡧ૭ͰϑΟϧλʔͷSyntaxΛิ׬ͯ͘͠ΕΔ

• Syntax reference

• https://developers.google.com/code-search/reference

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ߦ਺͕ଟ͍ίʔυͰ΋αΫαΫදࣔ͞ΕΔ
• 1ສߦ͘Β͍ͷίʔυͳΒಡΈࠐΈ΋දࣔ΋αΫαΫ

• ࢼ͠ʹIntent.javaΛ։͍ͯΈͯʂ

• https://cs.android.com/android/platform/
superproject/+/master:frameworks/base/core/java/
android/content/Intent.java

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ϒϥϯνͷ੾Γସ͕͑Ͱ͖Δ
• ಛఆOSόʔδϣϯͷಈ࡞Λௐ΂͍ͨ࣌ʹศར

• ݹ͍OSόʔδϣϯͷϒϥϯν΋͋Δ

• ίʔυΛ։͍ͨ··ϒϥϯν੾Γସ͑Ͱɺ੾Γସ͑ઌͷ
 
όʔδϣϯͷίʔυʹมΘΔ

• ͦͷ͏ͪAndroid 12ͷϒϥϯν΋ग़Δ͸ͣ

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ϒϥϯνͷ੾Γସ͕͑Ͱ͖Δ

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૬ޓࢀরͷϦϯΫ͕షΒΕ͍ͯΔ
• ϝιουɾΫϥεͳͲ΁ͷδϟϯϓ͕Ͱ͖Δ

• ίʔυʹϦϯΫ͕షΒΕ͍ͯΔͷͰͦΕΛΫϦοΫ͢Δ͚ͩ

• ͢΂ͯͷίʔυʹ૬ޓࢀরͷϦϯΫ͕͋ΔΘ͚͡Όͳ͍
 
ͷͰ஫ҙ

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https://cs.android.com/android/platform/superproject/+/android-11.0.0_r40:frameworks/base/core/java/android/app/
Activity.java;l=5070

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https://cs.android.com/android/platform/superproject/+/android-11.0.0_r40:frameworks/base/core/java/android/app/
Activity.java;drc=55d98d2ba142d6c35894b1092397e2b5a70bc2e8;l=3440

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ϝιουͷ֊૚ݺͼग़͠ɺࢀর͕Θ͔Δ
https://cs.android.com/android/platform/superproject/+/android-11.0.0_r40:frameworks/base/core/java/android/database/
sqlite/SQLiteDatabase.java;l=830;bpv=1;bpt=1

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ఆ਺΋ࢀর͞Ε͍ͯΔՕॴ͕Θ͔Δ
https://cs.android.com/android/platform/superproject/+/android-11.0.0_r40:frameworks/base/core/java/android/database/
sqlite/SQLiteGlobal.java;l=46;bpv=1;bpt=0

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• Ϋϥεʹఆٛͯ͋͠Δ
 
ఆ਺ɺϝιουͳͲ͕
 
ҰཡͰݟΕΔ
Ξ΢τϥΠϯΊͪΌศརʂ

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• ϑΟϧλʔ΋Ͱ͖Δʂ
Ξ΢τϥΠϯΊͪΌศརʂ

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• ΩʔϘʔυૢ࡞͚ͩͰ΋
͋Δఔ౓࢖͑ΔΑ͏ʹ
 
ߟྀ͞Εͯͦ͏
ΩʔϘʔυγϣʔτΧοτ

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• ৭ʑม͑ΒΕΔ

• ݕࡧ݁Ռ݅਺૿΍͢ͷ
 
͓͢͢Ί

• ࣗ෼ʹ߹ͬͨίʔυͷ
 
ϑΥϯταΠζʹมߋ͢Δ
Android Code Searchͷઃఆ

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Android Code Search ૢ࡞σϞ
• ࣮ࡍʹૢ࡞ͯ͠Δͱ͜ΖΛσϞ͠·͢

• ͥͻΈͳ͞Μ΋͓ࢼ͍ͩ͘͠͞ʂʂ

• https://cs.android.com/

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“Code Search for Google open source projects”
https://opensource.googleblog.com/2020/04/code-search-for-
google-open-source.html
Code Search͸Android͚ͩ͡Όͳ͍ʂ

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͜Μͳʹ͍ͬͺ͍ʂʂ
https://cs.opensource.google/

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Chromium΋͋Δ
https://source.chromium.org/chromium

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AOSP WebαΠτ
• AOSP(Android Open Source Project)

• https://source.android.com/index.html

• Androidͷ৭Μͳ͜ͱ͕υΩϡϝϯτͰ·ͱ·ͬͯΔ

• ڵຯ͋ΔςʔϚΛݟ͚ͭͯಡΜͰΈΔͷ͕͓͢͢Ί

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adb(Android Debug Bridge)
• ৭ʑศརͳadbίϚϯυ

• ୺຤ͷঢ়ଶΛ೺Ѳɾૢ࡞͢Δ্Ͱඞਢͳπʔϧ

• ࠓճ͸Code Reading͢Δࡍʹɺݸਓతʹར༻ස౓͕
 
ߴ͍ίϚϯυͷΈ঺հ

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adb(Android Debug Bridge)
• adbͷৄࡉ΍ઃఆͳͲ͸ҎԼͷϦϯΫΛݟ͍ͯͩ͘͞

• https://developer.android.com/studio/command-line/
adb

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Logcat
• AndroidγεςϜ͕ॻ͖ग़ͨ͠ϩάΛग़ྗ͢Δπʔϧ

• ϩά͸Code Readingʹ໾ཱͭૉࡐͷҰͭ

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“Android Logging System”
https://elinux.org/Android_Logging_System
Logcat

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• جຊ͜ΕɻΦϓγϣϯ͸ඞཁʹͳͬͨΒ࢖͏ɻ
Α͘࢖ͬͯΔLogcatίϚϯυྫ
> ~ adb logcat -v time

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• mainҎ֎ͷϩά͕ݟ͍ͨ৔߹ʹ͸ -b
Α͘࢖ͬͯΔLogcatίϚϯυྫ
> ~ adb logcat -v time -b system

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LogcatΛදࣔͭͭ͠ϑΝΠϧʹॻ͖ࠐΉ
• ϩάΛޙʑ·ͨݟ͍ͨ৔߹ʹศར

• aliasʹ͓ͯ͘͠ͱ͍͍
> ~ adb logcat -v time | tee logcat_main_$
(date +"%Y%m%d-%H%M%S").log

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“Logcat command-line tool”
https://developer.android.com/studio/command-line/logcat
LogcatͷΦϓγϣϯʹ͍ͭͯৄ͘͠

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• ϩάόοϑΝͷαΠζΛ
 
େ͖͘͢Δ

• ϩά͕ྲྀΕͯফ͑ͯ͠·͏
ͷΛܰݮͰ͖Δ

• ։ൃऀ޲͚Φϓγϣϯ͔Β
มߋͰ͖Δ
Logcatͷ͓͢͢Ίઃఆ

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Logcatͷ࣮૷
• ͜͜

superproject/+/master:system/logging/logcat/

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dumpsys
• γεςϜαʔϏεͷঢ়ଶΛग़ྗ͢Δπʔϧ

• γεςϜαʔϏεؔ࿈ͷCode ReadingΛ͢Δࡍʹศར

• ΞϓϦ։ൃ࣌ʹ΋໾ཱͭ

• https://developer.android.com/studio/command-line/
dumpsys

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dumpsys
• جຊతʹग़ྗ͍ͨ͠γεςϜαʔϏεΛࢦఆ͢Δ
> ~ adb shell dumpsys

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“pecoΛ࢖ͬͯಛఆͷγεςϜαʔϏεͷ

dumpsysΛ؆୯ʹ͢Δ”
https://qiita.com/operandoOS/items/
15bc6d1053d3ab31b300
dumpsys

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bugreport
• ৭Μͳϩά͔ΒCode ReadingͷώϯτΛಘΔ৔߹ʹศར

• औಘͰ͖Δϩάͷ਺͸ΊͬͪΌଟ͍
> ~ adb bugreport

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“Reading Bug Reports”
https://source.android.google.cn/setup/contribute/read-bug-
reports
bugreport

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• DroidKaigi 2017Ͱͻͨ͢
Βadbʹ͍ͭͯ࿩ͨ͠ͷͰ
ڵຯ͋Δํ͸ͥͻʂ

• https://speakerdeck.com/
operando/
komantonasitehokuhaan
droidkai-fa-tekinaihua-1
ͦͷଞͷadbίϚϯυʹ͍ͭͯ

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ಡΈ͍ͨ໨తͷίʔυʹ
 
ͨͲΓணٕ͘ज़

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ಡΈ͍ͨ໨తͷίʔυʹͨͲΓணٕ͘ज़
• Android Framework͸ίʔυྔ͕๲େͳͷͰద౰ʹ୳ͯ͠
΋ಡΈ͍ͨ໨తͷίʔυʹͨͲΓண͚ͳ͍😭

• ͖͞΄Ͳ঺հͨ͠αΠτ΍πʔϧΛར༻ͯ͠
 
ಡΈ͍ͨ໨తͷίʔυʹͨͲΓண͘ํ๏ͷྫΛ঺հ

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• Android Code SearchͷݕࡧΛ࢖͏

• LogcatͳͲγεςϜ͕ग़ྗ͢ΔϩάΛ࢖͏

• ΞϓϦ্ʹදࣔ͞ΕΔจࣈྻΛ࢖͏

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Android Code SearchͷݕࡧΛ࢖͏
• ಡΈ͍ͨ໨తͷίʔυʹؔ࿈ͦ͠͏ͳϫʔυͰݕࡧ͢Δ

• ͳΜͱͳ͘໨తͷίʔυͷ໨੕͕෇͍ͯΔ৔߹͸
 
͜Ε͕Ұ൪ૣ͍͔΋

• ݕࡧ݁Ռ͕ଟ͗͢Δ৔߹͸ɺݕࡧϑΟϧλʔΛ׆༻ͯ͠
 
݅਺Λߜ͍ͬͯ͘

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• ͖͞΄Ͳ঺հͨ͠Logcat
ͷϩάόοϑΝαΠζΛ
 
ม͑Δ࣮૷Λ୳ͨ͠ྫ

• languageϑΟϧλʔ͸
 
͓͢͢Ί
ݕࡧϑΟϧλʔΛ׆༻ͯ݅͠਺ΛߜΔ

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“Rust in the Android platform”
https://security.googleblog.com/2021/04/rust-in-android-
platform.html
AndroidͷRustͬͯͲ͜Ͱ࢖ΘΕͯΔͷʁ

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AndroidͷRustͬͯͲ͜Ͱ࢖ΘΕͯΔͷʁ

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LogcatͳͲγεςϜ͕ग़ྗ͢ΔϩάΛ࢖͏
• खࠒͳͷ͸Logcatͷग़ྗΛ࢖͏΍Γํ

• γεςϜ͕ग़ྗ͢Δϩά = ϩάग़ྗͷίʔυ͕ଘࡏ͢Δ

• ग़ྗ͍ͯ͠ΔίʔυʹͨͲΓண͖ɺͦͷपลͷίʔυ͔Β
໨తͷίʔυ΁ͨͲΓண͚Δ͔୳͢

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͜ΜͳखॱͰϩάΛ࢖ͬͯίʔυΛ୳͢
1. ಡΈ͍ͨ໨తͷίʔυʹؔ࿈͢Δૢ࡞Λߦ͏

2. ૢ࡞1ʹΑΓग़ྗ͞ΕͨLogcat͔ΒಡΈ͍ͨίʔυʹ
 
ؔ࿈͢ΔϩάΛ୳͢

3. ݟ͚ͭͨϩά͔ΒݻఆจࣈྻΛ୳͢

4. ݟ͚ͭͨจࣈྻΛAndroid Code Search(ACS)Ͱݕࡧ͢Δ

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͜ΜͳखॱͰϩάΛ࢖ͬͯίʔυΛ୳͢
• ʮΞϓϦ͕ΞϯΠϯετʔϧ͞ΕΔ࣌ʹߦΘΕ͍ͯΔ͜ͱʯ
ΛಡΈ͍ͨ໨తͷίʔυͱͯ͠ɺ۩ମతʹखॱΛઆ໌

• ࢿྉΛݟͳ͕ΒΈͳ͞ΜͷखݩͰ࣮ࡍʹ΍ͬͯΈΔ͜ͱΛ
 
͓͢͢Ί͠·͢

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• ૢ࡞࣌ͷϩά͕ݟ͍ͨͷͰɺLogcatίϚϯυΛ࣮ߦ͓ͯ͘͠
> ~ adb logcat -v time

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• ʮΞϓϦ͕ΞϯΠϯετʔϧ͞
ΕΔ࣌ʹߦΘΕ͍ͯΔ͜ͱʯΛ
஌Γ͍ͨͷͰɺ୺຤͔Βద౰ʹ
ΞϓϦΛΞϯΠϯετʔϧ͢Δ

• ͜Ε͕ʮಡΈ͍ͨ໨తͷίʔυ
ʹؔ࿈͢Δૢ࡞ʯͰ͢

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2. ಡΈ͍ͨίʔυʹؔ࿈͢ΔϩάΛ୳͢
• ૢ࡞1ʹΑΓग़ྗ͞ΕͨLogcat͔ΒಡΈ͍ͨίʔυʹ
 
ؔ࿈͢ΔϩάΛ୳͢

• ஍ຯʹ໨grepྗ͕໰ΘΕΔ

• ϩάग़ྗͷྔ͕ଟ͍ૢ࡞ͷ৔߹͸ϑΝΠϧʹॻ͖ग़্ͨ͠Ͱ
୳͢ํ͕͍͍

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• ؔ࿈ͦ͠͏ͳϩάൃݟ
2. ಡΈ͍ͨίʔυʹؔ࿈͢ΔϩάΛ୳͢

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UninstallerActivity(19960):Uninstallingextras=Bundle[{com.an
droid.packageinstaller.extra.APP_LABEL=DroidKaigi2021,com.
android.packageinstaller.applicationInfo=ApplicationInfo{5f5c
cecio.github.droidkaigi.feeder.debug},android.intent.extra.UN
INSTALL_ALL_USERS=false,
com.android.packageinstaller.extra.UNINSTALL_ID=-2147483
643}]
 
I/ActivityManager( 1424): Force stopping
io.github.droidkaigi.feeder.debug appid=10666 user=0:
deletePackageX

I/ActivityManager( 1424): Killing
23256:io.github.droidkaigi.feeder.debug/u0a666 (adj 940):
stop io.github.droidkaigi.feeder.debug due to deletePackageX
• ԫ৭෦෼͸ݻఆจࣈྻͬΆ͍
งғؾ

• tagʢUninstallerActivityͷ
෦෼ʣ͸ݻఆจࣈྻͰίʔυ
্ʹఆٛ͞Ε͍ͯΔ͜ͱ͕ଟ
͍ͷͰݕࡧʹ࢖͍΍͍͢
3. ݟ͚ͭͨϩά͔ΒݻఆจࣈྻΛ୳͢

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• ظ଴Ͳ͓Γ͍͍ײ͡ʹݕࡧ
ʹҾ͔͔ͬΓ·ͨ͠

• ݕࡧʹώοτͨ͠ίʔυΛ
ى఺ʹಡΈ͍ͨ໨తͷ
 
ίʔυΛ஍ಓʹ୳͢
4. ݟ͚ͭͨจࣈྻΛACSͰݕࡧ͢Δ

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γεςϜ͕ग़ྗ͢ΔϩάͰ࢖͑ͦ͏ͳ΋ͷ
• γεςϜαʔϏεͷίʔυΛಡΉͳΒdumpsysͷϩάΛ
 
࢖͏ͷ͕͓͢͢Ί

• ৭Μͳϩά͔Β୳͢ͳΒbugreportΛ࢖͏ͷ͕͓͢͢Ί

• ಡΈ͍ͨίʔυʹΑͬͯ࢖͑Δϩά͸ଞʹ΋৭ʑ͋Δ

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ΞϓϦ্ʹදࣔ͞ΕΔจࣈྻΛ࢖͏
1. ಡΈ͍ͨ໨తͷίʔυʹؔ࿈͢ΔΞϓϦΛ୳͢

2. ૢ࡞1Ͱݟ͚ͭͨΞϓϦͰಡΈ͍ͨίʔυʹ
 
ɹؔ࿈͢Δը໘Λ୳͢

3. ݟ͚ͭͨը໘͔ΒݻఆจࣈྻΛ୳͢

4. ݟ͚ͭͨจࣈྻΛAndroid Code Search(ACS)Ͱݕࡧ͢Δ

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• ʮΞϓϦ͕ڧ੍ఀࢭ͞ΕΔ࣌ʹߦΘΕΔ͜ͱʯ
 
ΛಡΈ͍ͨ໨తͷίʔυͱͯ͠ɺ۩ମతͳखॱΛઆ໌

• ࢿྉΛݟͳ͕ΒΈͳ͞ΜͷखݩͰ࣮ࡍʹ΍ͬͯΈΔ͜ͱΛ
 
͓͢͢Ί͠·͢
ΞϓϦ্ʹදࣔ͞ΕΔจࣈྻΛ࢖͏

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• ʮΞϓϦ͕ڧ੍ఀࢭ͞ΕΔ࣌ʹߦΘΕΔ͜ͱʯ͕஌Γ͍ͨͷ
ͰɺઃఆΞϓϦ͕ྑͦ͞͏
1. ಡΈ͍ͨ໨తͷίʔυʹؔ࿈͢ΔΞϓϦΛ୳͢

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• ʮΞϓϦ͕ڧ੍ఀࢭ͞ΕΔ
࣌ʹߦΘΕΔ͜ͱʯ͕஌Γ
͍ͨͷͰɺઃఆΞϓϦͷ
 
͜ͷը໘͕ྑͦ͞͏
2. ಡΈ͍ͨίʔυʹؔ࿈͢Δը໘Λ୳͢

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• ʮڧ੍ఀࢭ͠·͔͢ʁʯ͸
ݻఆจࣈྻͬΆ͍ͷͰ
 
ݕࡧͷૉࡐʹ͠·͠ΐ͏
3. ݟ͚ͭͨը໘͔ΒݻఆจࣈྻΛ୳͢

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• ݕࡧͯ͠ແࣄώοτ͠·ͨ͠

• ACS೔ຊޠͷݕࡧ΋໰୊ͳ͘ಈ͘ͷΑ͍ʂ

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• ΞϓϦจݴ͸ݕࡧ͢Δͱߴ֬཰Ͱstrings.xml͕ώοτ͢Δ

• ώοτͨ͠stringͷnameͰ͞Βʹݕࡧ͢Δ

• nameͰݕࡧ͢Δͱදࣔͯ͠Δ࣮૷ʹͨͲΓண͘

• ͔ͦ͜ΒपลͷίʔυΛಡΜͰ͍͘

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• ͍͍ײ͡ʹݕࡧʹώοτͨ͠

• language:javaΛ͚ͭͯ
stirngs.xml͕ݕࡧ݁Ռʹ
 
Ҿ͔͔ͬΒͳ͍Α͏ʹͯ͠Δ

• ݕࡧʹώοτͨ͠ίʔυΛى఺
ʹಡΈ͍ͨ໨తͷ
 
ίʔυΛ஍ಓʹ୳͢

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Android FrameworkͰ
 
ΞϓϦ։ൃऀ͕खܰʹ
 
ಡΊͦ͏ͳίʔυͷ঺հ

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frameworks/
• Android Framework Layerશൠͷίʔυ

superproject/+/master:frameworks/

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frameworks/base/services/core/
• γεςϜαʔϏεͷίʔυ

superproject/+/master:frameworks/base/services/
core/

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frameworks/base/core/java/
• Android SDKશൠͷίʔυ

superproject/+/master:frameworks/base/core/java/

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packages/apps/
• γεςϜΞϓϦશൠͷίʔυ

superproject/+/master:packages/apps/

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ΞϓϦ։ൃऀ͕खܰʹಡΊͦ͏ͳίʔυ
• Android Framework Layer͸C/C++ͷίʔυ΋Ұ෦͋Γ
·͕͢ɺJavaͷίʔυ΋ΊͬͪΌ͋ΔͷͰಡΈ๞͖Δ͜ͱ
͸ͳ͍ͱࢥ͍·͢ʂ

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Code Readingͷ݁ՌΛ
 
·ͱΊΔ

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Code Readingͷ݁ՌΛ·ͱΊΔ
• ·ͱΊͨ݁Ռ͸͖ͬͱ୭͔ͷ໾ʹཱͪ·͢☺

• ·ͱΊ͓ͯ͘ͱࣗ෼͕ݟฦ࣌͢ʹศར👍

• ·ͱΊͯͲ͔͜ʹެ։͓ͯ͘͠ͷ͕͓͢͢ΊͰ͢✨

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Code Readingͷ݁ՌΛͲ͏·ͱΊΔ͔
• Code Readingͨ͠ର৅ͷ֓ཁΛهࡌ͢Δ

• Code Readingͨ͠ཧ༝ͱΘ͔ͬͨ͜ͱͷཁ໿Λهࡌ͢Δ

• ॏཁͳ࣮૷෦෼͸ίʔυ෇͖ͰϝϞΔ + ίʔυͷϦϯΫΛ͚ͭΔ

• ࢀߟʹͳΔυΩϡϝϯτͷϦϯΫΛషΔ

• Code Reading࠷தϝϞΛ࢒͠ɺͦΕ΋ͬ͟ͱهࡌ͢Δ

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• ͦΕͧΕͷ޻ఔʹ͍ͭͯɺࢲ͕ҎલCode Readingͯ͠
 
݁ՌΛ·ͱΊͨهࣄΛྫʹઆ໌͠·͢

• ·ͱΊΔࡍͷࢀߟʹͳΕ͹ͱ✨

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“Android11͔Βಋೖ͞ΕͨAuto-reset
permissionsΛௐ΂ͯΈͯΘ͔ͬͨ͜ͱ”
https://hack-it-iron.hatenablog.com/entry/
2020/12/14/081217

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• ॏཁͳ෦෼͸ίʔυͱίʔυ΁ͷϦϯΫΛهࡌ͢Δ

• ࢀߟʹͳΔυΩϡϝϯτͷϦϯΫΛهࡌ͢Δ


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• ର৅͕ಛఆͷػೳͰ͋Ε͹
 
ͦͷػೳͷ֓ཁΛهࡌ͢Δ

• ֓ཁ͕ॻ͍ͯ͋ΔͱCode
Readingͨ݁͠Ռͷ·ͱΊ
΋ཧղ͠΍͘͢ͳΔ
Code Readingͨ͠ର৅ͷ֓ཁΛهࡌ͢Δ

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• ཧ༝Λॻ͘ͱ໨తʹ͋ͬͨ
 
ίʔυΛಡΉ͜ͱʹ
 
ूதͰ͖Δ

• Θ͔ͬͨ͜ͱͷཁ໿Λ
 
ॻ͘ͱ·ͱΊΛಡΈฦ͢
 
ࡍʹศར
ཧ༝ͱΘ͔ͬͨ͜ͱͷཁ໿Λهࡌ͢Δ

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• Code Readingͷ·ͱΊจ
ষ͚ͩͰ఻͑Δͷ͸೉͍͠

• ࣮૷෦෼ͷίʔυ΋ަ͑ͯ
·ͱΊΔͷ͕͓͢͢Ί

• ίʔυ΁ͷϦϯΫ΋Ұॹʹ
͋Δͱͳ͓Α͍👍
ίʔυͱίʔυ΁ͷϦϯΫΛهࡌ͢Δ

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• Code Reading͍ͯ͠Δத
ͰࢀߟʹͳΓͦ͏ͳυΩϡ
ϝϯτ͋Ε͹ɺඞཁͳͱ͜
ΖͰهࡌ͢Δ

• ࢀߟϦϯΫूΈ͍ͨͳܗͰ
࠷ޙͷํʹ·ͱΊͯهࡌ
 
͢Δͷ΋͋Γ
ࢀߟʹͳΔυΩϡϝϯτͷϦϯΫΛهࡌ͢Δ

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• Code ReadingதϝϞΛ࢒͠ɺͦΕ΋ͬ͟ͱهࡌ͢Δ

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• Code Reading͢Δ্Ͱ
 
ϝϞ͸େࣄ

• ͪΐͬͱͨ͠ϝϞͰ΋ফͣ͞
ʹ࢒͓ͯ͘͠

• ·ͱΊͷ࠷ޙͷํʹϝϞΛ
 
ͦͷ··ࡶʹॻ͍͓͚ͯͩ͘
Ͱ΋Ձ஋͸͋Δ
ϝϞΛ࢒͠ɺͦΕ΋ͬ͟ͱهࡌ͢Δ
https://github.com/operando/JobScheduler-Code-Reading

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·ͱΊ

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·ͱΊ
• Android Frameworkͷίʔυ͸ಡΉςΫχοΫΛ਎ʹ
 
͚ͭΕ͹ɺΘΓͱ͢ΜͳΓಡΊΔΑ͏ʹͳΓ·͢💪

• ͨͩίʔυྔ͕๲େͳͷͰࠜؾڧ͞͸ඞཁͰ͢😅

• ಡΜͩΒ·ͱΊΛॻ͍ͯ஌ݟΛڞ༗͠·͠ΐ͏👍

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Thank you!

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͜ΕҎ߱͸ొஃ࣌ؒͷ౎߹Ͱ
࡟ͬͨεϥΠυू

ʢ͓·͚ʣ

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Android Framework Code Readingͷ
 
ώϯτʹͳΔॻ੶
• AndroidΛࢧ͑Δٕज़ʪⅠʫ,ʪⅡʫ

• Androidͷͳ͔Έ InsideAndroid

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Android FrameworkͷίʔυΛμ΢ϯϩʔυ͢Δ
• Repoͱ͍͏πʔϧΛ࢖͏͜ͱͰμ΢ϯϩʔυͰ͖Δ

• Android OSΛ։ൃ͢Δ্Ͱ͸ඞਢͳπʔϧ

• ৭ʑେมͳͷͰຊฤͰͷ঺հΛආ͚ͨ😂

• https://source.android.google.cn/setup/build/
downloading

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adb-peco
• ෳ਺AndroidσόΠε͕PCʹ઀ଓ͞Ε͍ͯΔ࣌ʹ
 
σόΠεબ୒Λࢧԉͯ͘͠ΕΔπʔϧ

• https://github.com/tomorrowkey/adb-peco

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AIDEGen
• Android Frameworkͷ։ൃΛIDEͰߦ͏ͨΊʹ৭ʑ΍ͬͯ
͘ΕΔπʔϧͬΆ͍

• https://android.googlesource.com/platform/tools/
asuite/+/refs/heads/master/aidegen/README.md

• ࢖ͬͨ͜ͱͳ͍͚ͲɺࢿྉΛ࡞ͬͯΔաఔͰݟ͚ͭͨ

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AIDEGen
https://codechacha.com/ja/android-aidegen/
“AIDEGenʹIDEͰAndroid Framework։ൃ”

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Session Buddy
• Chrome Extension

• https://sessionbuddy.com/

• ։͍ͯΔλϒΛλϒɾ΢Οϯυ΢ͷঢ়ଶΛอଘͰ͖Δ

• Code Readingͯ͠ΔͱΊͬͪΌλϒ։͖·͘Δ

• ಡΜͰΔঢ়ଶΛҰ୴อଘ͓͖͍ͯͨ͠৔߹ʹศར

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πϦʔܕλϒ
• Firefox Add-ons

• https://addons.mozilla.org/ja/
fi
refox/addon/tree-
style-tab/

• ಡΜͰ͍Δίʔυͷϝιουݺͼग़͠ͷ֊૚ͱ͔ΛπϦʔ
ܕͷλϒͰ؅ཧ͢Δͷʹศར

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ͪΐͬͱੲ࿩ͱײँͷؾ࣋ͪ
• ACS͕ެ։͞ΕΔલ͸༗ࢤʹΑΔӡӦͰɺOpenGrokͱ͍
͏ιϑτ΢ΣΞΛ࢖ͬͯࣅͨ΋ͷ͕ߏங͞Ε͍ͯͨ

• https://sites.google.com/site/devcollaboration/
codesearch

• ͱͯ΋͓ੈ࿩ʹͳΓ·ͨ͠🙏͘͢͝ײँ͍ͯ͠·͢ʂ

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·ͬͨΓAndroid Framework Code Reading
• AndroidͷιʔείʔυΛಡΜͰɺ։ൃ౳ʹ໾ཱͯΔษڧձΛ
 
਺೥લ ࢲ͕ओ࠵ऀͰ΍͍ͬͯͨ

• ࢀՃऀͷΈͳ͞Μ͕ಡΜͩίʔυΛ·ͱΊͨͷ͕GitHubʹ·ͱ·ͬͯΔ

• Կ͔ͷࢀߟʹͳΕ͹ͱʂ

• https://github.com/AndroidFrameworkCodeReading/
CodeReadingHistory

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できる！Android Framework Code Reading

できる！Android Framework Code Reading

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