StrictMode policy violation: android.os.StrictMode$StrictModeDiskReadViolation: policy=327711 violation=2 at Application super.onCreate

Question

When I turn on the strict mode detect All, my App crashes super.onCreate() of application (i.e. before even I have any of my code doing anything).

My application onCreate turning on the strict mode as below

override fun onCreate() {
    if (BuildConfig.DEBUG) {
        StrictMode.setThreadPolicy(
                StrictMode.ThreadPolicy.Builder()
                        .detectAll()
                        .penaltyLog()
                        .penaltyDeath().build())
        StrictMode.setVmPolicy(
                StrictMode.VmPolicy.Builder()
                        .detectAll()
                        .penaltyLog()
                        .penaltyDeath().build())
    }
    super.onCreate()

    // Some other code
}

The error I got (which is on the line of super.onCreate())

D/StrictMode: StrictMode policy violation; ~duration=98 ms: android.os.StrictMode$StrictModeDiskReadViolation: policy=327711 violation=2
                                                             at android.os.StrictMode$AndroidBlockGuardPolicy.onReadFromDisk(StrictMode.java:1263)
                                                             at libcore.io.BlockGuardOs.open(BlockGuardOs.java:182)
                                                             at libcore.io.IoBridge.open(IoBridge.java:438)
                                                             at java.io.FileInputStream.<init>(FileInputStream.java:76)
                                                             at android.graphics.Typeface.getFullFlipFont(Typeface.java:584)
                                                             at android.graphics.Typeface.getFontPathFlipFont(Typeface.java:532)
                                                             at android.graphics.Typeface.SetFlipFonts(Typeface.java:719)
                                                             at android.graphics.Typeface.SetAppTypeFace(Typeface.java:846)
                                                             at android.app.Application.onCreate(Application.java:110)
                                                             at com.mypackage.MyApplication.onCreate(MyApplication.kt:40)

Is this an expected error we should ignore, or is this something that we should fix?

Line 40 of `onCreate` is reading from the disk(`onReadFromDisk`). — Jared Burrows, Jul 18 '16 at 01:41
That's the `super.onCreate` of the application. What can I do about that? — Elye, Jul 18 '16 at 01:42
Nothing. Just focus on the `StrictMode` violations from the code that you have written. — Jared Burrows, Jul 18 '16 at 01:43
Oh thanks. Is there a way to suppress these error/warning, so that the strictmode would only check the code of my package/module? — Elye, Jul 18 '16 at 01:52
Not that I know of. See this to try and filter them: http://stackoverflow.com/questions/25056157/filter-android-strictmode-violations-by-duration. — Jared Burrows, Jul 18 '16 at 02:01
Thanks @Jared. I have got a way to suppress it in coding. https://medium.com/@elye.project/android-strict-mode-selective-code-suppression-37ee0d999f6b#.rfcyw3n5j — Elye, Jul 20 '16 at 03:14
Sure, posted my answer. If you like it, you could give a vote to it :) Cheers! — Elye, Jul 20 '16 at 04:12

score 5 · Accepted Answer · edited Apr 18 '18 at 13:10

Apparently the error are device specific. It happens on Samsung S7, but not Nexus 6P. Hence it's not something I would be fixing. Hence the best way to suppress it.

The below is the example how I got it suppressed. You could wrap those functions into an Util Class.

override fun onCreate() {
    turnOnStrictMode()
    permitDiskReads{
        super.onCreate()
    }

    // Some other code
}


fun turnOnStrictMode() {
    if (BuildConfig.DEBUG) {
        StrictMode.setThreadPolicy(
                StrictMode.ThreadPolicy.Builder()
                        .detectAll()
                        .penaltyLog()
                        .penaltyDeath().build())
        StrictMode.setVmPolicy(
                StrictMode.VmPolicy.Builder()
                        .detectAll()
                        .penaltyLog()
                        .penaltyDeath().build())
    }
}

fun permitDiskReads(func: () -> Any) : Any {
    if (BuildConfig.DEBUG) {
        val oldThreadPolicy = StrictMode.getThreadPolicy()
        StrictMode.setThreadPolicy(
                StrictMode.ThreadPolicy.Builder(oldThreadPolicy)
                .permitDiskReads().build())
        val anyValue = func()
        StrictMode.setThreadPolicy(oldThreadPolicy)

        return anyValue
    } else {
        return func()
    }
}

Refers to this for more detail.

Just make sure you do not do any diskreads: `permitDiskReads`. — Jared Burrows, Jul 20 '16 at 04:19
The permitDiskReads only applies to the code that is sent to the function, after that the checks turn on again for all through the `StrictMode.setThreadPolicy(oldThreadPolicy)` — Elye, Jul 20 '16 at 04:42

score 2 · Answer 2 · answered Aug 13 '18 at 19:33

2

Move the statement 'super.onCreate()' before the StrictMode methods in fun onCreate(). Check this article for details. Walk through hell with Android StrictMode

answered Aug 13 '18 at 19:33

Sanju Varghese

487
2
4

score 0 · Answer 3 · answered Feb 07 '20 at 10:31

Here is my Java version

public class StrictModeManager {

private static boolean enabled = false;

private StrictModeManager() {}

public static void enableStrictMode() {
    enabled = true;
    StrictMode.ThreadPolicy.Builder threadPolicyBuilder = new StrictMode.ThreadPolicy.Builder()
            .detectDiskReads()
            .detectDiskWrites()
            .detectNetwork()
            .penaltyLog()
            .penaltyDropBox();

    StrictMode.VmPolicy.Builder vmPolicyBuilder = new StrictMode.VmPolicy.Builder()
            .detectLeakedSqlLiteObjects()
            .detectLeakedClosableObjects()
            .detectLeakedRegistrationObjects()
            .penaltyLog()
            .penaltyDropBox()
            .penaltyDeath();

    StrictMode.setThreadPolicy(threadPolicyBuilder.build());
    StrictMode.setVmPolicy(vmPolicyBuilder.build());

}

public static void allowDiskReads(Runnable runnable) {
    StrictMode.ThreadPolicy oldThreadPolicy = null;
    if (enabled) {
        oldThreadPolicy = StrictMode.getThreadPolicy();
        StrictMode.setThreadPolicy(new StrictMode.ThreadPolicy.Builder(oldThreadPolicy).permitDiskReads().build());
    }
    runnable.run();
    if (oldThreadPolicy != null) StrictMode.setThreadPolicy(oldThreadPolicy);
   }
}

And to use it:

@Override
public void onCreate() {
    if (BuildConfig.DEBUG) StrictModeManager.enableStrictMode();
    StrictModeManager.allowDiskReads(App.super::onCreate);

    // Code here
}

Not working out-of-the-box. On java, the 'App.super::onCreate' is not being recognized and I cannot think of good way to cast Runnable to/from the super in this case. — HX_unbanned, Jan 30 '22 at 12:19

StrictMode policy violation: android.os.StrictMode$StrictModeDiskReadViolation: policy=327711 violation=2 at Application super.onCreate

3 Answers3

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