sun.misc.Contended is not a member of package sun.misc Scala

I'm updating JDK version from 8 to 11 an get the issue with some concurrent data structure.

error: type Contended is not a member of package sun.misc
[ERROR] @sun.misc.Contended
[ERROR]           ^
[ERROR] one error found

Is there a way to work around this? I'm using Scala 2.12.8?

If you're using this annotation in your user code, you should just remove it, as it's not doing anything.

Hotspot allows use of this annotation in privileged code. From classFileParser.cpp:

AnnotationCollector::ID
AnnotationCollector::annotation_index(const ClassLoaderData* loader_data,
                                      const Symbol* name) {
  const vmSymbols::SID sid = vmSymbols::find_sid(name);
  // Privileged code can use all annotations.  Other code silently drops some.
  const bool privileged = loader_data->is_the_null_class_loader_data() ||
                          loader_data->is_platform_class_loader_data() ||
                          loader_data->is_anonymous();
  switch (sid) {
...
    case vmSymbols::VM_SYMBOL_ENUM_NAME(jdk_internal_vm_annotation_Contended_signature): {
      if (_location != _in_field && _location != _in_class) {
        break;  // only allow for fields and classes
      }
      if (!EnableContended || (RestrictContended && !privileged)) {
        break;  // honor privileges
      }
      return _jdk_internal_vm_annotation_Contended;
    }

If the annotation is used outside of privileged code it is normally ignored.

But! it looks like there is a production level flag to enable @Contended specifically for non-privileged classes.

In that case you can use --add-exports java.base/jdk.internal.vm.annotation=<your module> when compiling, and import the annotation from jdk.internal.vm.annotation instead.

Then when running the application use -XX:-RestrictContended.

Of course this is an internal API that should rather not be depended upon. However, for migration to later versions of Java, the above flags can be used as a temporary solution.