Description
Java 18 comes with several changes that are expected to cause warnings or other problems: email. Expected problems include warnings about use of the now deprecated SecurityManager.
A test run with OpenJDK 18 results in an error during compilation due to plugin incompatibility.
Task: Find and fix problems with JDK 18.
See also: https://issues.apache.org/jira/browse/DERBY-7126, https://issues.apache.org/jira/browse/DERBY-7137, https://issues.apache.org/jira/browse/DERBY-7138