Java Programming

Study the codes given below or copy and save as Test.java then compile, execute and check out the result.
Is this mistake of sun people or what?
If anybody claims, that is not mistake or some kind of leap adjustments please explain it how and why, I’m quite eager to know about it?
And if that is real mistake can anyone imagine how much that mistake can affect big science projects like astronomy etc? Which has based in java?
java version "1.6.0_04"


import java.util.*;
import java.text.*;
public class Test
{
public static void main(String[] args)
{
GregorianCalendar Date_A = new GregorianCalendar(1941,9,1,0,0,0); //Early (Wednesday, Oct 1 1941 00:00:00).
GregorianCalendar Date_B = new GregorianCalendar(1941,9,1,0,36,39);//Late (Wednesday, Oct 1 1941 00:36:39).
GregorianCalendar Date_C = new GregorianCalendar(1941,9,1,0,36,40);//Late (Wednesday, Oct 1 1941 00:36:40).
SimpleDateFormat df = new SimpleDateFormat("EEEEEEEE, MMM dd yyyy HH:mm:ss.aaa ");
long gdt1 = Date_A.getTimeInMillis();
long gdt2 = Date_B.getTimeInMillis();
long gdt3 = Date_C.getTimeInMillis();
Date da = new Date(gdt1);
System.out.println("A: (Wednesday, Oct 1 1941 00:00:00) = "+df.format(da));
Date db = new Date(gdt2);
System.out.println("B: (Wednesday, Oct 1 1941 00:36:39) = "+df.format(db));
Date dc = new Date(gdt3);
System.out.println("C: (Wednesday, Oct 1 1941 00:36:40) = "+df.format(dc));

long difMilsA2B = gdt2-gdt1;
long difMilsA2C = gdt3-gdt1;
long difDays,difHour,difMin,difSec,rmdMils;

difDays = difMilsA2B/86400000;
rmdMils = difMilsA2B-(difDays*86400000);
difHour = rmdMils/3600000;
rmdMils = rmdMils-(difHour*3600000);
difMin = rmdMils/60000;
rmdMils = rmdMils-(difMin*60000);
difSec = rmdMils/1000;
rmdMils = rmdMils-(difSec*1000);

String rslt= difDays+" Day, "+difHour+" Hr, "+difMin+" Min, "+difSec+" Sec, "+rmdMils+" Millis.";
System.out.println("\n(Date_B - Date_A) = "+difMilsA2B+" Milliseconds\n |\n |\n -->> "+rslt);

difDays = difMilsA2C/86400000;
rmdMils = difMilsA2C-(difDays*86400000);
difHour = rmdMils/3600000;
rmdMils = rmdMils-(difHour*3600000);
difMin = rmdMils/60000;
rmdMils = rmdMils-(difMin*60000);
difSec = rmdMils/1000;
rmdMils = rmdMils-(difSec*1000);

rslt= difDays+" Day, "+difHour+" Hr, "+difMin+" Min, "+difSec+" Sec, "+rmdMils+" Millis.";
System.out.println("\n\n(Date_C - Date_A) = "+difMilsA2C+" Milliseconds\n |\n |\n -->> "+rslt);
}
}
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At present (New Delhi, India)
Email: rajjajue@yahoo.com
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