ProGuard

Slides from Android Tech Talks #9 meetup at @techspacekrk

1. PROGUARD
2. chalup.github.io ! " + @jchalupski +Jerzy Chalupski
3. PROGUARD
4. Hello, world!
5. dependencies {
 
 }
6. $ g assembleDebug
 Total time: 1.908 secs
 
 $ du -h ./app-debug.apk
 24K ./app-debug.apk
7. dependencies {
 compile ‘google-play-services'
 }
8. $ g assembleDebug
 Total time: 3.014 secs
 
 $ du -h ./app-debug.apk
 1.8M ./app-debug.apk
9. $ g assembleDebug
 Total time: 3.014 secs
 
 $ du -h ./app-debug.apk
 1.8M ./app-debug.apk $ tar -xzvf app-debug.apk
 
 $ du -h -d 0 classes.dex res
 3.8M classes.dex
 592K res
10. ! futuresimple/dex-method-counts
11. $ dexcount ./app-debug.apk
 android.support.v4: 6285
 com.google.ads: 124
 com.google.android.gms: 22730
 org.chalup.proguardtechtalk: 18
12. #YOLO
13. dependencies {
 compile ‘google-play-services’ compile ‘support.*’ compile ‘guava’ compile ‘gson’ compile ‘joda-time’ compile ‘square.*’ compile ‘butterknife’ compile ‘rxjava’ compile ‘rxandroid’ compile ‘android-arsenal.*’ }
14. $ g assembleDebug
 :app:dexDebug FAILED
 
 UNEXPECTED TOP-LEVEL EXCEPTION:
 DexIndexOverflowException method ID not in [0, 0xffff]
15. dependencies {
 compile ‘support.multidex’ } buildTypes {
 debug {
 multiDexEnabled true
 }
 }

16. $ g assembleDebug

17. $ g assembleDebug BUILD SUCCESSFUL
18. $ g assembleDebug BUILD SUCCESSFUL 
 Total time: 48.784 secs

19. $ g assembleDebug BUILD SUCCESSFUL 
 Total time: 48.784 secs
 $ du -h ./app-debug.apk
 7.5M ./app-debug.apk
20. $ g assembleDebug BUILD SUCCESSFUL 
 Total time: 48.784 secs
 $ du -h ./app-debug.apk
 7.5M ./app-debug.apk $ dexcount ./app-debug.apk Total method count: 81986

21. @Override
 protected void attachBaseContext(Context c) {
 super.attachBaseContext(c);
 
 MultiDex.install(this);
 }
22. @Override
 protected void attachBaseContext(Context c) {
 super.attachBaseContext(c);
 long start = System.currentTimeMillis();
 MultiDex.install(this);
 long end = System.currentTimeMillis(); long elapsed = end - start;
 Log.d(TAG, “multidex: " + elapsed + "ms");
 }
23. @Override
 protected void attachBaseContext(Context c) {
 super.attachBaseContext(c);
 long start = System.currentTimeMillis();
 MultiDex.install(this);
 long end = System.currentTimeMillis(); long elapsed = end - start;
 Log.d(TAG, “multidex: " + elapsed + "ms");
 } 252ms on Samsung S5 with KitKat at 66k methods
24. @Override
 protected void attachBaseContext(Context c) {
 super.attachBaseContext(c);
 long start = System.currentTimeMillis();
 MultiDex.install(this);
 long end = System.currentTimeMillis(); long elapsed = end - start;
 Log.d(TAG, “multidex: " + elapsed + "ms");
 } 1083ms on Samsung S5 with KitKat at 81k methods
25. @Override
 protected void attachBaseContext(Context c) {
 super.attachBaseContext(c);
 long start = System.currentTimeMillis();
 MultiDex.install(this);
 long end = System.currentTimeMillis(); long elapsed = end - start;
 Log.d(TAG, “multidex: " + elapsed + "ms");
 } ~4000ms on Nexus 5 with KitKat at ~130k methods
26. @Override
 protected void attachBaseContext(Context c) {
 super.attachBaseContext(c);
 long start = System.currentTimeMillis();
 MultiDex.install(this);
 long end = System.currentTimeMillis(); long elapsed = end - start;
 Log.d(TAG, “multidex: " + elapsed + "ms");
 } 2ms on Nexus 5 with Lollipop at 81k methods
27. TAKEAWAY #1 multidex is not a silver bullet
28. PROGUARD?
29. dependencies {
 
 }
30. $ dexcount ./app-debug.apk <root>: 15
 android.app: 2
 java.lang: 2
 org.chalup.proguardtechtalk: 11
31. buildTypes {
 all {
 minifyEnabled true
 proguardFiles = [
 getDefaultProguardFile( ‘proguard-android.txt' ),
 'proguard-rules.pro'
 ]
 }
 }

32. $ dexcount ./app-debug.apk <root>: 5
 android.app: 2
 org.chalup.proguardtechtalk: 3
33. dependencies {
 compile ‘google-play-services'
 }
34. $ dexcount ./app-debug.apk android: 1874
 com.google.android.gms: 6453
 java: 381
 org.chalup.proguardtechtalk: 3
 org.json: 13
 
 Total method count: 8726
35. buildTypes {
 all {
 minifyEnabled true
 proguardFiles = [
 getDefaultProguardFile( ‘proguard-android.txt' ),
 'proguard-rules.pro'
 ]
 }
 }

36. $ANDROID_HOME/tools/proguard/proguard-android.txt --keep class * implements android.os.Parcelable { - public static final android.os.Parcelable$Creator *; +-keepnames class * implements android.os.Parcelable { + public static final ** CREATOR;
37. $ANDROID_HOME/tools/proguard/proguard-android.txt --keep class * implements android.os.Parcelable { - public static final android.os.Parcelable$Creator *; +-keepnames class * implements android.os.Parcelable { + public static final ** CREATOR; “OK ProGuard, please keep all Parcelables”
38. $ANDROID_HOME/tools/proguard/proguard-android.txt --keep class * implements android.os.Parcelable { - public static final android.os.Parcelable$Creator *; +-keepnames class * implements android.os.Parcelable { + public static final ** CREATOR; “OK ProGuard, please keep all *USED* Parcelables”
39. $ANDROID_HOME/tools/proguard/proguard-android.txt --keep class * implements android.os.Parcelable { - public static final android.os.Parcelable$Creator *; +-keepnames class * implements android.os.Parcelable { + public static final ** CREATOR; http://proguard.sourceforge.net/manual/usage.html
40. buildTypes {
 all {
 minifyEnabled true
 proguardFiles ‘copypasta-rules.pro'
 }
 }

41. $ dexcount ./app-debug.apk <root>: 5
 android.app: 2
 org.chalup.proguardtechtalk: 3
42. $ du -h ./app-debug.apk
 554K ./app-debug.apk
43. buildTypes {
 all {
 minifyEnabled true
 proguardFiles ‘copypasta-rules.pro'
 }
 }

44. buildTypes {
 all {
 minifyEnabled true shrinkResources true
 proguardFiles ‘copypasta-rules.pro'
 }
 }

45. $ du -h ./app-debug.apk
 228K ./app-debug.apk
46. $ du -h ./app-debug.apk
 228K ./app-debug.apk https://code.google.com/p/android/issues/detail?id=80872
47. TAKEAWAY #2 Tune getDefaultProguardFile
48. PROGUARD Y U NO PRUNE?
49. dependencies {
 compile ‘google-play-services’ compile 'appcompat-v7'
 }
50. $ dexcount ./app-debug.apk android: 3173
 java: 125
 org.chalup.proguardtechtalk: 3
 org.xmlpull.v1: 3
 
 Total method count: 3304
51. $ dexcount ./app-debug.apk android: 3173
 graphics: 53
 support: 2584
 v4: 652
 v7: 1932
 internal: 1298
 widget: 621
 view: 201
 widget: 162
52. $ cat build/ intermediates/ proguard-rules/ debug/ aapt_rules.txt 
 # view AndroidManifest.xml #generated:16
 -keep class org.chalup.proguardtechtalk.MainActivity { <init>(...); }
 
 # view res/layout/abc_action_menu_item_layout.xml #generated:17
 -keep class android.support.v7.internal.view.menu.ActionMenuItemView { <init>(...); }
53. TAKEAWAY #3 you can’t prune 100% of unused code in UI libs
54. PROGUARD Y U NO KEEP?
55. dependencies {
 compile ‘google-play-services’ compile ‘appcompat-v7' compile 'butterknife'
 }
56. public class MainActivity extends Activity {
 
 @InjectView(R.id.hello_text)
 TextView mTextView;
 
 @Override
 protected void onCreate(Bundle state) {
 super.onCreate(state);
 setContentView(R.layout.activity_main);
 
 ButterKnife.inject(this);
 mTextView.setText(R.string.hello_world);
 }
 }
57. AndroidRuntime D Shutting down VM E FATAL EXCEPTION: main E Process: org.chalup.proguardtechtalk, PID: 21061 E java.lang.RuntimeException: Unable to start activity ComponentInfo{…}: java.lang.NullPointerException: E at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2298) E at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360) E at android.app.ActivityThread.access$800(ActivityThread.java:144) E at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278) E at android.os.Handler.dispatchMessage(Handler.java:102) E at android.os.Looper.loop(Looper.java:135) E at android.app.ActivityThread.main(ActivityThread.java:5221) E at java.lang.reflect.Method.invoke(Native Method) E at java.lang.reflect.Method.invoke(Method.java:372) E at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899) E at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694) E Caused by: java.lang.NullPointerException: E at org.chalup.proguardtechtalk.MainActivity.onCreate(Unknown Source) E at android.app.Activity.performCreate(Activity.java:5933) E at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105) E at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2251) E ... 10 more
58. +-dontwarn butterknife.internal.** +-keep class **$$ViewInjector { + *; +} +-keepnames class * { + @butterknife.InjectView *; +}
59. TAKEAWAY #4 @ + ProGuard = troubles
60. TAKEAWAY #4 @ + ProGuard = troubles https://github.com/krschultz/android-proguard-snippets
61. TAKEAWAY #4 @ + ProGuard = troubles https://bitbucket.org/littlerobots/squadleader
62. apply plugin: 'com.android.library'
 
 android {
 defaultConfig {
 consumerProguardFiles ‘…’
 }
 } https://bitbucket.org/littlerobots/squadleader
63. TAKEAWAY #5 Writing a library? Provide ProGuard config!
64. PROGUARD!
65. dependencies {
 compile ‘google-play-services’ compile ‘support.*’ compile ‘guava’ compile ‘gson’ compile ‘joda-time’ compile ‘square.*’ compile ‘butterknife’ compile ‘rxjava’ compile ‘rxandroid’ compile ‘android-arsenal.*’ }
66. $ g assembleDebug
67. $ g assembleDebug BUILD SUCCESSFUL 
 Total time: 16.096 secs

68. $ g assembleDebug BUILD SUCCESSFUL 
 Total time: 16.096 secs
 $ du -h ./app-debug.apk
 3.5M ./app-debug.apk
69. $ g assembleDebug BUILD SUCCESSFUL 
 Total time: 16.096 secs
 $ du -h ./app-debug.apk
 3.5M ./app-debug.apk $ dexcount ./app-debug.apk Total method count: 6636

70. $ g assembleDebug BUILD SUCCESSFUL 
 Total time: 48.784 secs
 $ du -h ./app-debug.apk
 7.5M ./app-debug.apk $ dexcount ./app-debug.apk android.support.v4: 81986

71. $ g assembleDebug BUILD SUCCESSFUL 
 Total time: 16.096 secs
 $ du -h ./app-debug.apk
 3.5M ./app-debug.apk $ dexcount ./app-debug.apk Total method count: 6636

72. - multiDexEnabled true
73. $ g assembleDebug BUILD SUCCESSFUL 
 Total time: 15.049 secs
 $ du -h ./app-debug.apk
 3.5M ./app-debug.apk $ dexcount ./app-debug.apk Total method count: 6539

74. TAKEAWAY #6 Good ProGuard config FTW!
75. GOTCHA #1
76. -dontobfuscate -dontoptimize $ g assembleDebug BUILD SUCCESSFUL
77. # -dontobfuscate -dontoptimize $ g assembleDebug BUILD SUCCESSFUL
78. -dontobfuscate $ g assembleDebug :app:dexDebug FAILED EXCEPTION FROM SIMULATION: local variable type mismatch: Ph'nglui mglw’nafh Cthulhu R'lyeh wgah'nagl fhtagn
79. -dontobfuscate -optimizations !code/allocation/variable
80. -dontobfuscate -optimizations !code/allocation/variable $ g assembleDebug BUILD SUCCESSFUL
81. http://stackoverflow.com/a/7587680/184953 -dontobfuscate -optimizations !code/allocation/variable $ g assembleDebug BUILD SUCCESSFUL
82. GOTCHA #2
83. LinkedHashMultimap<Integer, String> map =
 LinkedHashMultimap.create(); 
 map.put(1, "1");
 map.put(1, "2");
 map.put(1, "3");
 
 Collection<String> data = map.asMap().get(1);
 Log.d("JCH", new Gson().toJson(data));
84. E FATAL EXCEPTION: main E Process: org.chalup.proguardtechtalk, PID: 31243 E java.lang.reflect.GenericSignatureFormatError E at libcore.reflect.GenericSignatureParser.expect(GenericSignatureParser.java:473) E at libcore.reflect.GenericSignatureParser.parseClassTypeSignature(GenericSignatureParser.java:332) E at libcore.reflect.GenericSignatureParser.parseClassSignature(GenericSignatureParser.java:234) E at libcore.reflect.GenericSignatureParser.parseForClass(GenericSignatureParser.java:126) E at java.lang.Class.getGenericInterfaces(Class.java:1134) E at com.google.gson.internal.$Gson$Types.getGenericSupertype($Gson$Types.java:238) E at com.google.gson.internal.$Gson$Types.getSupertype($Gson$Types.java:269) E at com.google.gson.internal.$Gson$Types.getCollectionElementType($Gson$Types.java:288) E at com.google.gson.internal.bind.CollectionTypeAdapterFactory.create(CollectionTypeAdapterFactory.java:51) E at com.google.gson.Gson.getAdapter(Gson.java:359) E at com.google.gson.Gson.toJson(Gson.java:592) E at com.google.gson.Gson.toJson(Gson.java:579) E at com.google.gson.Gson.toJson(Gson.java:534) E at com.google.gson.Gson.toJson(Gson.java:514) E at org.chalup.proguardtechtalk.MainActivity.getString(MainActivity.java:40) E at org.chalup.proguardtechtalk.MainActivity.onCreate(MainActivity.java:36) E at android.app.Activity.performCreate(Activity.java:5933)
85. buildscript {
 repositories {
 jcenter()
 }
 dependencies {
 classpath 'com.android.tools.build:gradle:1.0.1'
 }
 }
86. buildscript {
 repositories {
 jcenter()
 }
 dependencies {
 classpath 'com.android.tools.build:gradle:1.0.1'
 }
 configurations.all {
 resolutionStrategy {
 force 'net.sf.proguard:proguard-gradle:4.11'
 }
 }
 }
87. buildscript {
 repositories {
 jcenter()
 }
 dependencies {
 classpath 'com.android.tools.build:gradle:1.0.1'
 }
 configurations.all {
 resolutionStrategy {
 force 'net.sf.proguard:proguard-gradle:4.11'
 }
 }
 } NOTE: this is top level build.gradle, not module one
88. GOTCHA #3
89. # Release ProGuard config -assumenosideeffects class android.util.Log {
 public static *** d(...);
 }

90. @Override
 protected void onCreate(Bundle state) {
 super.onCreate(state);
 setContentView(R.layout.activity_main);
 
 Log.d(TAG, doNotRunOnProduction());
 }
 
 private String doNotRunOnProduction() {
 Log.e(TAG, "FIRE ZE MISSILES!");
 
 return "Harmless log message";
 }

91. E FIRE ZE MISSILES! D Harmless log message $ g assembleDebug
92. @Override
 protected void onCreate(Bundle state) {
 super.onCreate(state);
 setContentView(R.layout.activity_main);
 
 Log.d(TAG, doNotRunOnProduction());
 }
 
 private String doNotRunOnProduction() {
 Log.e(TAG, "FIRE ZE MISSILES!");
 
 return "Harmless log message";
 }

93. E FIRE ZE MISSILES! $ g assembleRelease
94. @Override
 protected void onCreate(Bundle state) {
 super.onCreate(state);
 setContentView(R.layout.activity_main);
 
 Log.d(TAG, doNotRunOnProduction());
 }
 
 private String doNotRunOnProduction() {
 Log.e(TAG, "FIRE ZE MISSILES!");
 
 return "Harmless log message";
 }

95. @Override
 protected void onCreate(Bundle state) {
 super.onCreate(state);
 setContentView(R.layout.activity_main);
 String tmp = doNotRunOnProduction();
 Log.d(TAG, tmp);
 }
 
 private String doNotRunOnProduction() {
 Log.e(TAG, "FIRE ZE MISSILES!");
 
 return "Harmless log message";
 }

96. @Override
 protected void onCreate(Bundle state) {
 super.onCreate(state);
 setContentView(R.layout.activity_main);
 String tmp = doNotRunOnProduction();
 // Log.d(TAG, tmp); pruned by ProGuard
 }
 
 private String doNotRunOnProduction() {
 Log.e(TAG, "FIRE ZE MISSILES!");
 
 return "Harmless log message";
 }

97. http://chalup.github.io/blog/2013/08/20/proguard-gotcha/ E FIRE ZE MISSILES! $ g assembleRelease
98. TAKEAWAY #7 Beware of gotchas
99. RECAP
100. TAKEAWAY #1 multidex is not a silver bullet
101. TAKEAWAY #2 Tune getDefaultProguardFile
102. TAKEAWAY #3 you can’t prune 100% of unused code in UI libs
103. TAKEAWAY #4 @ + ProGuard = troubles
104. TAKEAWAY #5 Writing a library? Provide ProGuard config!
105. TAKEAWAY #6 Good ProGuard config FTW!
106. TAKEAWAY #7 Beware of gotchas
107. ?
108. Thanks.