Develop Reference

Is there any way to disable Proguard configuration output?

I use this in each module of my multi-module library project
proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), '../proguard-rules-library.pro'
Is there any way I can disable configuration outputs to console on build stage? This is an example:
The proguard configuration file for the following section is C:\Users\pc\Development\project\build\app\intermediates\default_proguard_files\global\proguard-android.txt-7.2.2
This is a configuration file for ProGuard.
http://proguard.sourceforge.net/index.html#manual/usage.html
This is just a part of a log output. It goes on further with printing the contents of my proguard-rules-library.pro files
P.S. there is no -printconfiguration flag in the file, but default proguard-android-optimize has the -verbose flag. But I don't think it could be the cause of such behavior

You can remove logging calls with this option in proguard-project.txt:
-assumenosideeffects class android.util.Log {
public static boolean isLoggable(java.lang.String, int);
public static int v(...);
public static int i(...);
public static int w(...);
public static int d(...);
public static int e(...);
}
This option is relevant if optimization is not disabled, like in proguard-android.txt. You have to specify proguard-android-optimize.txt instead, in project.properties:
proguard.config=${sdk.dir}/tools/proguard/proguard-android-optimize.txt:proguard-project.txt

stream was reset: null

I had a strange bug which was hard to find :-(
In my Android app I use Retrofit2 with Moshi do access an api. I also use proguard-android-optimize.txt to make my app clean and small. And in my proguard-rules.pro I have:
-assumenosideeffects class timber.log.Timber { *; }
-assumenosideeffects class android.util.Log { *; }
With this combination I get this error stream was reset: null when I try to access the api.
To fix it I have to remove this assumenosideeffects lines from my proguard config. But why? Has anyone an idea why I get this network problem when proguard removes logging methods?

The wildcard * matches all methods, including methods in super classes, like Object#wait(). You don't really want to remove those invocations, so you should explicitly list the methods for which you want to remove the invocations:
-assumenosideeffects class android.util.Log {
public static boolean isLoggable(java.lang.String, int);
public static int v(...);
public static int i(...);
public static int w(...);
public static int d(...);
public static int e(...);
}
ProGuard already prints out a warning if you specify the wildcard.

Use ProGuard to exclude Log in Android

Is it possible to exclude the implementation of Log class from the apk using ProGuard during the build generation? So when we generate an apk, we do not have the development Logs in the class files.

Yes, you can remove logs.
-assumenosideeffects class android.util.Log {
public static boolean isLoggable(java.lang.String, int);
public static int v(...);
public static int i(...);
public static int w(...);
public static int d(...);
public static int e(...);
}
more information: Removing Log call using proguard

Dexguard security during debugging

i am using Dexguard in my android application to protect from
reverse engineering.Now in my application which is very big ,i have
used several places System.out.println in many classes in which i am
printing my server URL to debugg for my ease.Now when i am releasing
this application ,and this apk i am giving to other developers ,they
can see all the System.out.println things in their logcat. how
should i avoid that. This has serious issue.

First of all you shouldn't be using System.out.println directly everywhere. Use your own wrapper class for logging.
In dexguard/proguard you can use assumenosideeffects for removing codes that are unnecessary for release.
So for System.out.print you can add following in your dexguard rules.
-assumenosideeffects class java.io.PrintStream {
public void println(%);
public void println(**);
}
But this is risky as this class might be used for purposes other than logging.
Fastest way for you would be to use android.util.Log in place of System.out.print and then add following
-assumenosideeffects class android.util.Log {
public static boolean isLoggable(java.lang.String, int);
public static int v(...);
public static int i(...);
public static int w(...);
public static int d(...);
public static int e(...);
}
See proguard docs

good answer by #vKashyap, you might also want to add this as well...
-assumenosideeffects class java.lang.Exception {
public void printStackTrace();
}

Removing Log call using proguard

I am trying to use proguard to strip all my logs:
I have entered the following line in my proguard-project.txt:
-assumenosideeffects class android.util.Log { *; }
And my project.properties looks like this:
proguard.config=${sdk.dir}/tools/proguard/proguard-android.txt:proguard-project.txt
Inspite of this the logs continue to show in my application. What exactly am I doing wrong here?

You shouldn't specify the '*' wildcard, because that includes methods like 'Object#wait()'. Better explicitly list the methods:
-assumenosideeffects class android.util.Log {
public static boolean isLoggable(java.lang.String, int);
public static int v(...);
public static int i(...);
public static int w(...);
public static int d(...);
public static int e(...);
}
This option is only relevant if optimization is not disabled, like in proguard-android.txt. You have to specify proguard-android-optimize.txt instead:
proguard.config=${sdk.dir}/tools/proguard/proguard-android-optimize.txt:proguard-project.txt
or with the contemporary Android Gradle plugin
buildTypes {
releaseSomeBuildType {
...
proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'your-proguard-file.pro'
}
}

It's pretty late and I came across the same problem. I am using Android studio 1.3 and this is what I did.
Add the log methods that you want to strip in your release build in proguard-android-optimize.txt:
-assumenosideeffects class android.util.Log {
public static boolean isLoggable(java.lang.String, int);
public static int d(...);
public static int w(...);
public static int v(...);
public static int i(...);
}
In your build.gradle (Module: app) set proguard-android-optimize.txt as default proguard file instead of proguard-android.txt:
buildTypes {
release {
minifyEnabled true
debuggable false
proguardFiles getDefaultProguardFile('proguard-android-optimize.txt')
}
}
This is because in proguard-android.txt optimization is turned off by default with flags
-dontoptimize
-dontpreverify
This worked for me, hope it helps others.

You need to do it like this:
-assumenosideeffects class android.util.Log {
public static int d(...);
public static int v(...);
public static int i(...);
public static int w(...);
public static int e(...);
public static int wtf(...);
}
and expand for all the log methods you are using.