Android R8 does not obfuscate a member name

Question

I have this code:

import static com.example.test.Utils.getPackageManagerReflection;
...

public class MainActivity extends AppCompatActivity {
    ...

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);

        PackageManager packageManagerReflection;
        try {
            packageManagerReflection = getPackageManagerReflection(...);
        } catch (NoSuchMethodException e) {
            e.printStackTrace();
        } catch (InvocationTargetException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        }
        if(packageManagerReflection == null) {
            finish();
            return;
        }
    }

    ...
}

com.example.test.Utils.getPackageManagerReflection:

public static <A, B> B getPackageManagerReflection(A param1, Class<B> param2, byte[] param2, Object param4) throws NoSuchMethodException, InvocationTargetException, IllegalAccessException {
    ...
}

Analyzing the generated apk with Android Studio, in classes.dex there is packageManagerReflection clearly readable, but getPackageManagerReflection doesn't:

.line 225
    .end local v2    # "packageManagerReflection":Landroid/content/pm/PackageManager;
    .end local v3    # "deviceId":Ljava/lang/String;
    .end local v5    # "exception":Ljava/lang/IllegalArgumentException;
    :catch_301
    move-exception v2

.line 231
    .local v2, "packageManagerReflection":Landroid/content/pm/PackageManager;
    nop

I'm using the latest version of Android Studio and all its components.

Why the name for member packageManagerReflection is keeped in the generated code?

I already tried to rename it to something different without reflection in its name (e.g. packageManagerRef but it still compare in classes.dex.

I also already seen in seeds.txt, mapping.txt and usage.txt in app/build/outputs/mapping/debug but there is no occurrence for it.

Thanks a lot!

score 2 · Accepted Answer · answered Mar 27 '20 at 20:07

2

Local variable names would be expected to be stripped in release versions of an app, they aren't necessary for execution (and aren't available through reflection). Thus, R8 wouldn't need to and doesn't rename them. Try looking for the same information in a release build, it shouldn't be present.

answered Mar 27 '20 at 20:07

neuralmer

573
3
11

Thanks, I'll give it a try as soon as possible! – user2342558 Mar 27 '20 at 20:17
Yesss! You're true! Thanks a lot! – user2342558 Mar 28 '20 at 15:01

Android R8 does not obfuscate a member name

1 Answers1