Stream: hapi
Topic: convert List of IBaseResource to List of Resources
Luca Toldo (Jan 21 2020 at 15:56):
Dear HAPIsts,
I need to generate a List of Resource, from a List of IBaseResource.
(List<Resource>) BundleUtil.toListOfResources(myBundle);
I was expecting it to be compatible with a simple cast since Resource implements IBaseResource ...
Any advice ?
Ian Bacher (Jan 21 2020 at 16:20):
Type erasure basically means that List<Resource> is not an instance of List<IBaseResource>, but even if that weren't the case, what you're trying to do would be unsafe as all Resources implement IBaseResource but IBaseResources are not necessarily assignable to the Resource type.
However, I think you can do what you want in a type-safe manner like so (assuming you're using Java 8 or newer):
BundleUtil.toListOfResources(myBundle).stream().filter(Resource.class::isInstance).map(Resource.class::cast).collect( Collectors.toList());
Luca Toldo (Jan 21 2020 at 16:24):
@Ian Bacher thankyou however now I get another error ...
BaseRuntimeElementDefinition cannot be cast to BaseRuntimeElementCompositeDefinition
Ian Bacher (Jan 23 2020 at 15:20):
BaseRuntimeElementDefinition cannot be cast to BaseRuntimeElementCompositeDefinition
Can you provide an example of what you're trying to do when you get this error?
Last updated: Apr 12 2022 at 19:14 UTC
