Bug 37992 - I keep getting error when proguard is enabled:
Summary: I keep getting error when proguard is enabled:
Alias: None
Product: Android
Classification: Xamarin
Component: BCL Class Libraries ()
Version: unspecified
Hardware: PC Windows
: --- normal
Target Milestone: ---
Assignee: Atsushi Eno
Depends on:
Reported: 2016-01-25 13:46 UTC by Sam
Modified: 2016-02-08 09:28 UTC (History)
1 user (show)

Is this bug a regression?: ---
Last known good build:

Shows the build errors (475.79 KB, text/plain)
2016-01-25 13:46 UTC, Sam

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Description Sam 2016-01-25 13:46:32 UTC
Created attachment 14716 [details]
Shows the build errors

down vote
Hi I'm trying to reduce my app size by enabling proguard. I keep getting error when proguard is enabled:

Java.exe exited with code 1. File: Xamarin.Android.Common.targets.
All the posts online refer to Gradle, but not sure what gradle means, i think its some kind of plugin but i'm not using that...

Any ideas on a fix? It was working previously with the same project so it is unusual.
Comment 1 Sam 2016-01-25 14:57:24 UTC
.cfg file


# This is Xamarin-specific (and enhanced) configuration.


-keep class mono.MonoRuntimeProvider
-keep class mono.MonoPackageManager
-keep class mono.MonoPackageManager_Resources
-keep class mono.android.**
-keep class mono.java.**
-keep class mono.javax.**
-keep class opentk.platform.android.AndroidGameView
-keep class opentk.GameViewBase
-keep class opentk_1_0.platform.android.AndroidGameView
-keep class opentk_1_0.GameViewBase
# hash for android.runtime
-keep class md52ce486a14f4bcd95899665e9d932190b.**
-keepclassmembers class md52ce486a14f4bcd95899665e9d932190b.** {

# Android's template misses fluent setters...
-keepclassmembers class * extends android.view.View {
   *** set*(***);

# also misses those inflated custom layout stuff from xml...
-keepclassmembers class * extends android.view.View {
Comment 2 Atsushi Eno 2016-02-08 09:28:59 UTC
Everything is described in your build output. There is a lot of warning messages from proguard output, and it ends up with this: 

>    java.io.IOException: Please correct the above warnings first.
>    	at proguard.Initializer.execute(Initializer.java:321)
>    	at proguard.ProGuard.initialize(ProGuard.java:211)
>    	at proguard.ProGuard.execute(ProGuard.java:86)
>    	at proguard.ProGuard.main(ProGuard.java:492)

What are those warnings? I found those ones (but not limited to those) problematic:

>    PROGUARD : warning : okio.DeflaterSink: can't find referenced class org.codehaus.mojo.animal_sniffer.IgnoreJRERequirement
>    PROGUARD : warning : okio.Okio: can't find referenced class java.nio.file.Files

The first line tells you didn't give additional jars to the project in any form (InputJar/EmbeddedJar/etc.).

The second line implies that the library you are trying to bind does NOT support Android, because its referencing API java.nio.file.Files does not exist on Android.