Comment From: snicoll
This release of HSQLDB switches the main artifact to Java 11. The release notes claim that it's released with a version for Java8 as well but I haven't found it on Maven Central. Given that the main artifact is Java 11 only, we won't be able to upgrade to it at this time.
Comment From: snicoll
Let's reuse this issue to upgrade to 2.5.2. We'll add a note for 2.6.x since it requires Java 11.
Comment From: philwebb
The docs say "HyperSQL version 2.6.0 is compatible with Java 11 or later and supports the Java module system. A version of the HSQLDB jar compiled with JDK 8 is also included in the download zip package" so I wonder if they aren't going to publish the Java 8 version to central.
Comment From: snicoll
Even if they did, it would be with different coordinates which constitutes a breaking change.