I recommend using OpenJDK 11 (download from:
https://www.b4x.com/b4j.html).
No need to create an Oracle account, it is newer, and it is compatible with B4J Packager 11 which is better than Oracle packager tool (wrapped by the old B4J Packager).
There is one advantage to Java 8, which is the support for executable jars. This is especially useful for small utilities.