[BUG] WARNING: Illegal reflective access by io.protostuff.runtime.PolymorphicThrowableSchema

[jcgraybill]

Describe the bug
In OpenSearch 1.1, the following warning is emitted in the logfiles when the Anomaly Detection plugin is installed:

WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by io.protostuff.runtime.PolymorphicThrowableSchema (file:/home/ec2-user/opensearch-1.1.0/plugins/opensearch-anomaly-detection/protostuff-runtime-1.7.4.jar) to field java.lang.Throwable.cause
WARNING: Please consider reporting this to the maintainers of io.protostuff.runtime.PolymorphicThrowableSchema
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

Let's clean this up.

Desktop (please complete the following information):

• OS: AL2 on EC2, x86_64
• OpenSearch 1.1

[kaituo]

This is a known issue of our dependency ProtoStuff since 2017: protostuff/protostuff#239

Currently, it is a warning and won't impact normal uses. But we will need to fix it either by fixing the warning by ourselves or using a different library.

[jcgraybill]

Let's fix one way or the other by 1.3.

[jcgraybill]

Hey, confirming, is this on track for 1.3?

[kaituo]

It is on track for 1.3 so far.

[ylwu-amzn]

Thanks @dblock to open issue to ask protostuff team to publish a new release protostuff/protostuff#327
And the suggestion.

Hand-building JARs is worse than this bug.
The library hasn't been worked on for a year, so we either will need to find an alternative or start contributing/maintaining.

[dblock]

Closed via #441, did not make it in 1.3, but will be in next.