Runtime exception below API 26 with unsupported Java nio API (with no lint error) [381126163]

Fixed

Bug

Status Update

No update yet.

Description

an...@steadfastinnovation.com

created issue #1

Nov 27, 2024 02:17AM

java.nio APIs can be used below API 26 with coreLibraryDesugaring "com.android.tools:desugar_jdk_libs_nio:2.1.3". However, as described in the java.nio customizations documentation:

The following is a list of features which aren't supported when the runtime device is strictly lower than API level 26. Calls to such APIs either return null or throw an instance of java.lang.UnsupportedOperationException.

java.nio.channels.AsynchronousFileChannel

Posix file features (group, owner, permissions), including reading or writing the attributes or attribute view or FileSystem#getUserPrincipalLookupService

Watch service, including FileSystem#newWatchService or Path#register

For example, running the following on API 21 produces a java.lang.UnsupportedOperationException:

Path path = new File("").toPath();

try(AsynchronousFileChannel open = AsynchronousFileChannel.open(path)) {
    open.read(ByteBuffer.allocate(1024), 1024);
} catch (IOException e) {
    throw new RuntimeException(e);
}

This is expected per the documentation, but is not discoverable except at runtime.

However, when using coreLibraryDesugaring "com.android.tools:desugar_jdk_libs:2.1.3" (the non-nio artifact), usages of this API (and all other java.nio APIs) produce lint errors unless wrapped in checks for API 26+.

Is it possible to show lint errors just for the APIs that will fail at runtime when they're not wrapped in API checks for API 26+ when using desugar_jdk_libs_nio? That way the build will fail rather than discovering this at runtime.

Comments

rk...@google.com <rk...@google.com> Nov 27, 2024 05:04PM

Assigned to an...@google.com.

tn...@google.com <tn...@google.com> #2Nov 27, 2024 05:26PM

Reassigned to sg...@google.com.

This should be moved to the Android Public Tracker > Text component, but I don't have permissions so I'm redirecting to the appropriate owner.

an...@steadfastinnovation.com <an...@steadfastinnovation.com> #3Nov 27, 2024 05:50PM

So after updating to 1.4.1 and all deps too, the crash was a little different see below.

The repro for that one is easy

create a new app from AS 7.1 RC 1
update deps to (Appcompat 1.4.1/Material 1.5.0/Constraintlayout 2.1.3)
Add 2 textViews

    <TextView
        android:id="@+id/text1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <TextView
        android:id="@+id/text2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/text1" />```

In onCreate:

        val t1 = findViewById<TextView>(R.id.text1)
        val t2 = findViewById<TextView>(R.id.text2)

        val charBuffer1 = CharArrayBuffer("AAA".toCharArray())
        charBuffer1.sizeCopied = 3
        val charBuffer2 = CharArrayBuffer("AAA".toCharArray())
        charBuffer2.sizeCopied = 3

        t1.setText(charBuffer1.data, 0, charBuffer1.sizeCopied)
        t2.setText(charBuffer2.data, 0, charBuffer2.sizeCopied)

Run see the texts updated then crash with the following. (Tested on P6 Pro Android 12)

Process: org.debug.myapplication, PID: 32493
    java.lang.NullPointerException: src == null
        at java.lang.System.arraycopy(Native Method)
        at android.widget.TextView$CharWrapper.getChars(TextView.java:13588)
        at android.text.TextUtils.getChars(TextUtils.java:155)
        at android.text.BoringLayout.hasAnyInterestingChars(BoringLayout.java:314)
        at android.text.BoringLayout.isBoring(BoringLayout.java:340)
        at android.widget.TextView.onMeasure(TextView.java:9413)
        at androidx.appcompat.widget.AppCompatTextView.onMeasure(AppCompatTextView.java:607)
        at android.view.View.measure(View.java:25774)
        at androidx.constraintlayout.widget.ConstraintLayout$Measurer.measure(ConstraintLayout.java:811)
        at androidx.constraintlayout.core.widgets.analyzer.BasicMeasure.measure(BasicMeasure.java:466)
        at androidx.constraintlayout.core.widgets.analyzer.BasicMeasure.measureChildren(BasicMeasure.java:134)
        at androidx.constraintlayout.core.widgets.analyzer.BasicMeasure.solverMeasure(BasicMeasure.java:278)
        at androidx.constraintlayout.core.widgets.ConstraintWidgetContainer.measure(ConstraintWidgetContainer.java:120)
        at androidx.constraintlayout.widget.ConstraintLayout.resolveSystem(ConstraintLayout.java:1594)
        at androidx.constraintlayout.widget.ConstraintLayout.onMeasure(ConstraintLayout.java:1708)
        at android.view.View.measure(View.java:25774)
        at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6980)
        at android.widget.FrameLayout.onMeasure(FrameLayout.java:194)
        at androidx.appcompat.widget.ContentFrameLayout.onMeasure(ContentFrameLayout.java:145)
        at android.view.View.measure(View.java:25774)
        at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6980)
        at androidx.appcompat.widget.ActionBarOverlayLayout.onMeasure(ActionBarOverlayLayout.java:496)
        at android.view.View.measure(View.java:25774)
        at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6980)
        at android.widget.FrameLayout.onMeasure(FrameLayout.java:194)
        at android.view.View.measure(View.java:25774)
        at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6980)
        at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1552)
        at android.widget.LinearLayout.measureVertical(LinearLayout.java:842)
        at android.widget.LinearLayout.onMeasure(LinearLayout.java:721)
        at android.view.View.measure(View.java:25774)
        at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6980)
        at android.widget.FrameLayout.onMeasure(FrameLayout.java:194)
        at com.android.internal.policy.DecorView.onMeasure(DecorView.java:761)
        at android.view.View.measure(View.java:25774)
        at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:3628)
        at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:2424)
        at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:2694)
        at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:2143)
        at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:8665)
        at android.view.Choreographer$CallbackRecord.run(Choreographer.java:1037)
        at android.view.Choreographer.doCallbacks(Choreographer.java:845)
        at android.view.Choreographer.doFrame(Choreographer.java:780)
        at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:1022)
        at android.os.Handler.handleCallback(Handler.java:938)
        at android.os.Handler.dispatchMessage(Handler.java:99)
        at android.os.Looper.loopOnce(Looper.java:201)
        at android.os.Looper.loop(Looper.java:288)
        at android.app.ActivityThread.main(ActivityThread.java:7839)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:548)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003)

sg...@google.com <sg...@google.com> #4Nov 28, 2024 09:58AM

Reassigned to cl...@google.com.

since it is possibly related to emojicompat reassigned

tn...@google.com <tn...@google.com> #5Nov 28, 2024 05:49PM

Thanks for the report.

What version of Android are you testing this on?

tn...@google.com <tn...@google.com> #6Dec 6, 2024 12:17AM

Marked as fixed, reassigned to tn...@google.com.

Android 12 P6 pro P3a and emulator A 11.

Can test on others the last repro is easy to test.

an...@google.com <an...@google.com> #7Dec 12, 2024 03:57PM

Thanks! That's helpful to know it's reproing on both 11 and 12 - no need to test on others. We'll have to explore a bit.