The Token Handler design pattern has attracted a lot of interest. The attention is explained by its usefulness in solving the challenge of securing Single Page Applications (SPAs) and improving user experience.
To help you with implementation, we have published several resources that we hope will be useful:
Token Handler End-to-End Tutorial
Single Page Application using the Token Handler code example
A tutorial describing the Token Handler implementation to facilitate development
Financial-Grade Token Handler code example
An example implementation of Token Handler component in Kotlin and Spring using some financial-grade features for increased security of OAuth flows.