I upgraded recently to the new Eclipse version (Oxygen). I downloaded the lombok.jar from the website and installed it. This is how the eclipse.ini looks like a
eclipse.ini
Also had problems with lombok in eclipse oxygen.
My solution: returned from java version 8u144 to 8u141.
And I refer to lombok by adding this to my eclipse.ini:
-Xbootclasspath/c:/DEV/Tools/lombok-1.16.18/lombok.jar
-javaagent:/DEV/Tools/lombok-1.16.18/lombok.jar