Serialisation of Durations

[ifly6]

It doesn't seem as if this adds a converter for java.time.Duration:

WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by com.google.gson.internal.reflect.ReflectionHelper 
    (file:/Users/ifly6/.m2/repository/com/google/code/gson/gson/2.9.1/gson-2.9.1.jar) to field
    java.time.Duration.seconds
WARNING: Please consider reporting this to the maintainers of com.google.gson.internal.reflect.ReflectionHelper
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release

Is that intentional?

[gkopff]

What code are you using to get that?