There is a lot of uncertainty about how the JDK will be distributed and updated. Oracle will continue to provide free public updates and auto updates of Java SE 8, until at least the end of December 2020 for Personal Users, and January 2019 for Commercial Users.
After those dates, you can either go onto a paid support or use a Java SE 8/ OpenJDK 8 binary distribution from another provider. You can also continue using Oracle JDK 8 indefinitely without updates. According to the scheduled quarterly critical patch update page, starting from April 2019 Oracle Customers can access updates to Java SE 8 for commercial use from Oracle through My Oracle Support and via corporate auto update.
What should I do to have free Java SE 8?
If you want updates of Java SE 8 after January 2019, use a different binary distribution of the OpenJDK, i.e., AdoptOpenJDK, Azul, OpenJDK, and others.
Given that JDK 8 free updates will end at the beginning of next year users should gravely consider how they will assure current and future deployed JDK versions maintenance for security and stability.
Have you decided what you will do?