Java 11 Compatibility

Date	2018 09 11	Contacts	María Arias de Reyna
Status	Research	Release	GeoNetwork 4.0
Resources	Initial research undertaken by GeoCat, expect additional activities to be required across the GeoNetwork community	Ticket #	OSGeo Java codesprint 2018
Source code	n/a
Funding	GeoCat providing initial assessment on behalf of GeoNetwork Enterprise product

Overview

The Java ecosystem is now lead by OpenJDK and has changed release cadence (two numbered release each year, with long-term-support releases every three years).

With this in mind there are two long-term-support releases:

Java 8 (LTS): 2014-2026 AdoptOpenJDK
Java 11 (LTS): 2018-2024 AdoptOpenJDK
Java 18 (LTS): 2021-TBA

Aside: We were initially concerned that Java 8 would no longer be supported, but an industry response lead by Red Hat, Eclipse Foundation and others is continuing to make OpenJDK 8 available to their customers and for Windows and macOS at http://adoptopenjdk.net.

Technical Details

2018 Initial Research

María Arias de Reyna participated in OSGeo Java 2018 Code Sprint:

OSGeo-Java-codesprint-2018

Results:

#. Naive Attempt: Run with maven/jetty

As expected Spring fails to load
Warnings on use of reflection "All illegal access operations will be denied in a future release"

#. Build with maven

Missing javax classes (and probably even more missing/moved core JDK classes
Warnings on use of reflection "All illegal access operations will be denied in a future release"

GeoNetwork cannot smoothly run on Java 11

Blocker:

A new release of GeoTools is needed: Java 9 introduced a restriction on Service Registry (used by the GeoTools library to coordinate plugins) a new release of GeoTools will be required before GeoNetwork can run on Java 11