なにげにFreeBSD4.6.2にjdk13ぶちこもうとしたら、
Patching file j2sdk1.3.1/src/solaris/native/sun/awt/robot_child/robot_proc.c using Plan A...
Hunk #1 succeeded at 25.
done
===> Applying FreeBSD patches for jdk-1.3.1p7_4
Ignoring previously applied (or reversed) patch.
1 out of 1 hunks ignored--saving rejects to ../ext/plugin/build/solaris/GNUmakefile.rej
>> Patch patch-GNUmakefile failed to apply cleanly.
*** Error code 1

Stop in /usr/ports/java/jdk13.
とかイワレマスタ。意味ワカンネー。