IssueTracker

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.