GeoIP performance: database expiration and InetAddress optimization

[dlvenable]

Description

From performance testing of the geoip processor I found two unrelated areas of unnecessary performance slowdowns.

Database expiration

The geoip processor was check if the database was expired for each event in a batch. This is a surprisingly slow operation because Instant.now() calls VM.getNanoTimeAdjustment(localOffset) which is somewhat slow.

This PR helps by adding a BatchGeoIPDatabaseReader which holds the value of isExpired for the whole batch. We don't re-evaluate for each event.

InetAddress optimization

Parsing the IP address is somewhat slow. The geoip processor was doing this twice. I consolidated this work into a single method GeoInetAddress::usableInetFromString which parses the string and then returns a non-empty Optional<InetAddress> if this IP address is usable (currently if it is public or not). Some of the refactoring here is also to make it more generic.

Finally, I moved the main processing into its own method to help with readability.

Issues Resolved

N/A

Check List

• New functionality includes testing.
• New functionality has a documentation issue. Please link to it in this PR.
  • New functionality has javadoc added
• Commits are signed with a real name per the DCO

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