FileMaker has declined to license Java on behalf of its customers or auto-migrate servers to OpenJDK.
As of February 2019, Oracle changed their licensing model to now require paid licenses in order to use Java in business and production capacities. The Java update started prompting people concerning this in April 2019. In the long term, FileMaker is getting rid of Java, but for now, FileMaker uses Java in three areas: FileMaker 16 and earlier admin console; FileMaker 17 and newer do not require it Custom Web Publishing (CWP) WebDirect
URL https://luminfire.com/2019/05/30/filemaker-java-licensing/