Below are the predefined variables you could use in the template settings such as java.templates.fileHeader and java.templates.typeComment.
${file_name}- name of the current Java file${package_name}- name of the enclosing package${type_name}- name of the current type${user}- current user system login name${date}- current system date${time}- current system time${year}- current year${month}- current month${shortmonth}- short form representation of current month${day}- current day of the month${hour}- current hour${minute}- current minute