System date, comparison of dates and adding dates to a field value of datetime type

// this extended rule explains how to take system date, compare it with date field from input data and also add some days to the field value  
object sysDate;
object sysDateFormat;
string[8] sysDateString;
datetime sysDate2;

sysDate = new("java.util.Date");
sysDateFormat = new("java.text.SimpleDateFormat","yyyyMMdd");
sysDateString = sysDateFormat.format(sysDate);

sysDate2 = date("%y%y%m%d",sysDateString);
if (#field_date < sysDate2) then
begin
   messagebox("date older than system date",0);
   #field_date = sysDate2 << days(7); 
end
   else
begin
   messagebox("date newer than system date",0);
end