Logstash 7.1.0 problem on Install

[kingram (Ken Ingram)]

Hardware: Raspbberry Pi3 (arm processor)
OS: Raspbian (Debian Stretch 9)
Java: openjdk 10

$ bin/logstash -e 'input { stdin {} } output { stdout {} }'
OpenJDK Server VM warning: Option UseConcMarkSweepGC was deprecated in version 9.0 and will likely be removed in a future release.
WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by com.headius.backport9.modules.Modules (file:/home/xxxxxxx/logstash-7.1.0/logstash-core/lib/jars/jruby-complete-9.2.7.0.jar) to field java.io.FileDescriptor.fd
WARNING: Please consider reporting this to the maintainers of com.headius.backport9.modules.Modules
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

What's going on here? How do I fix this error?

[Badger]

openjdk 10 is not supported. Try using Java 8.

[kingram (Ken Ingram)]

Or probably forward to 11, because I installed 10 for Elasticsearch.
The link to the support matrix was helpful though.

Going backward to openjdk 8 resolved the error, which suggests that it is a problem with jruby more than anything else.

Still didn't fix the problem though:

ERROR][org.logstash.Logstash ] java.lang.IllegalStateException: Logstash stopped processing because of an error: (LoadError) load error: ffi/ffi -- java.lang.NullPointerException: null

[Badger]

I cannot speak to why Java 10/11 might not work. I just know that other folks have posted about the "illegal reflective access" error and downgrading to Java 8 worked for them.

I know nothing about the "load error: ffi/ffi" error but I would note that a search for that in this forum finds a couple of occurrences, both on a Raspberry Pi.

And a search for Raspberry in this forum gives a set of results that does not look promising.