swi-prolog build failure: "cannot find java include files"

[anthony.hw.kong@…]

From the log file

:info:build checking if java works... yes
:info:build checking for jar... jar
:info:build checking for javadoc... javadoc
:info:build checking for javac... /usr/bin/javac
:info:build checking for javac... (cached) /usr/bin/javac
:info:build checking symlink for /usr/bin/javac... /System/Library/Frameworks/JavaVM.framework/Versions/Current/Commands/javac
:info:build configure: error: cannot find java include files
:info:build make[1]: *** [configure] Error 1
:info:build make: *** [.pkg-config] Error 2
:info:build shell command " cd "/opt/local/var/macports/build/_opt_local_var_macports_sources_rsync.macports.org_release_ports_lang_swi-prolog/work/pl-5.8.3" && /usr/bin/make all " returned error 2
:error:build Target org.macports.build returned: shell command failed
:debug:build Backtrace: shell command failed
    while executing
"command_exec build"
    (procedure "portbuild::build_main" line 8)
    invoked from within
"$procedure $targetname"